Files and Settings guide for Outlook

Files and Settings guide for Outlook
This guide is not for the faint hearted. If you are looking for a way to just backup your Outlook data, please take a look at this guide.
If you are looking for a way to conveniently backup your Outlook data
and settings or want to move your Outlook data and settings to another
computer, please take a look at this blog post.
If you are in IT support or just are interested to find out which files
Outlook uses and where it stores its settings; this is the guide for
you.
The files and settings are marked for possibilities to move to another computer or user profile in the following way;

• possible
• not needed (automatically recreated)
• not recommended (dependencies)
• not possible

"Not recommended", means that the single file could hold
dependencies on other settings, making it not usable after the
migration or could break something else. It could also mean that the
file holds data or settings which is automatically recreated after the
migration and therefore not required to migrate. If you want to move
these files, it is recommended that you use a backup/restore tool that
supports migrating these settings by also copying or taking out certain
dependencies. For that, please see this blog post.
Restoring it on the same computer for the same user is basically always possible unless otherwise specified.
To be able to view all files, folders and file extensions, you might need to make 3 changes first in;
Control Panel-> Folder Options-> tab View
-Show hidden files and folders (selected)
-Hide extensions for known file types (disabled)
-Hide protected operating system files (disabled; only needed to see contents of the Protect folder)
After finishing this guide, it is recommended to turn the options back to their original settings.
The files and settings guide is grouped in the following segments;

• Folder locations
• File names
• Registry locations

---

Folder locations
Unless otherwise specified, no advise is given to migrate the entire
folder to another machine because of its mixed contents. Look at the
list of individual files to determine if you can move the contents of
the folder as a whole or not.

Name	Description contents and Locations	Files
Main installation folder	Installation files and folders. For the main part this folders consists out of *.exe and *.dll files.	*.exe *.dll other installation files
	32-bit Windows: C:\Program Files\Microsoft Office\Office<version number>\ 64-bit Windows: C:\Program Files (x86)\Microsoft Office\Office<version number>\
Generic installation folder	Additional installation files and folders which are often shared between Office applications or other applications. For the main part this folders consists out of *.exe and *.dll files.	*.exe *.dll other installation files
	32-bit Windows: C:\Program Files\Common Files\Microsoft Shared\ 64-bit Windows: C:\Program Files (x86)\Common Files\Microsoft Shared\
Roaming Profile settings	Contains files and settings of the user which are being synced back to the server when Roaming Profiles is enabled in a domain.	<profilename>.nk2 <profilename>.srs <profilename>.xml outcmd.dat OutlPrnt VbaProject.OTM *.pab
	Windows XP: C:\Documents and Settings\%username%\Application Data\Microsoft\Outlook\ Windows Vista: C:\Users\%username%\AppData\Roaming\Microsoft\Outlook\
Local Profile settings	Contains files and settings of the user which are not being synced back to the server when Roaming Profiles in enabled in a domain.	<profilename>.sharing.xml.obi <profilename>.xml.kfl *.pst *.ost *.nst *.oab extend.dat
	Windows XP: C:\Documents and Settings\%username%\Local Settings\Application Data\Microsoft\Outlook\ Windows Vista: C:\Users\%username%\AppData\Local\Microsoft\Outlook\
Forms Roaming	Contains files with settings for the Form Designer in Outlook. Other (Office) applications can also use this location to store their own form design settings and data.	outlook.box RefEdit.exd
	Windows XP: C:\Documents and Settings\%username%\Application Data\Microsoft\Forms\ Windows Vista: C:\Users\%username%\AppData\Roaming\Microsoft\Forms\
Forms Local Cache	Here are forms cached which are not native or local to the Outlook environment. Usually these are custom forms from Public Folders. This folder holds a subfolder for each cached form. These folders are named after the message class and have a tmp-file within that folder.	FRMCACHE.DAT
	Windows XP: C:\Documents and Settings\%username%\Local Settings\Application Data\Microsoft\FORMS\ Windows Vista: C:\Users\%username%\AppData\Local\Microsoft\FORMS\
Protect	Folder with system files holding encrypted information. The folder is named after the Security ID (SID) of the user. It is used by Outlook 2003 and later and replaces the Protected Storage registry key. It is not possible to migrate this folder but removing this folder can solve mail account password issues on Windows Vista.	Encrypted data
	Windows XP: C:\Documents and Settings\%username%\Application Data\Microsoft\Protect\ Windows Vista: C:\Users\%username%\AppData\Roaming\Microsoft\Protect\
Signatures	Your signatures are being stored here in 3 formats; HTML, Plain Text and Rich Text The folder could hold additional data for your signature such as CSS, themes and images. For more on signatures see this guide.	*.htm *.txt *.rtf
	Windows XP: C:\Documents and Settings\%username%\Application Data\Microsoft\Signatures\ Windows Vista: C:\Users\%username%\AppData\Roaming\Microsoft\Signatures
Templates	Default folder to store templates in. This folder is shared with other Office applications and could hold additional files.	normal.dot normalemail.dotm
	Windows XP: C:\Documents and Settings\%username%\Application Data\Microsoft\Templates\ Windows Vista: C:\Users\%username%\AppData\Roaming\Microsoft\Templates
Stationery	Contains files used for personal stationery.	*.htm *.jpg *.gif other image formats
	Windows XP: C:\Documents and Settings\%username%\Application Data\Microsoft\Stationery\ Windows Vista: C:\Users\%username%\AppData\Roaming\Microsoft\Stationery\
Proof	Holds additional personal dictionaries in the ANSI format (Outlook 2003 and previous).	custom.dic
	Windows XP: C:\Documents and Settings\%username%\Application Data\Microsoft\Proof\ Windows Vista: C:\Users\%username%\AppData\Roaming\Microsoft\Proof\
UProof	Holds additional personal dictionaries in the UNICODE format (since Outlook 2007)	custom.dic
	Windows XP: C:\Documents and Settings\%username%\Application Data\Microsoft\UProof\ Windows Vista: C:\Users\%username%\AppData\Roaming\Microsoft\UProof\
Local Office Settings	Holds various local Office settings including your customizations to the Quick Access Toolbar in Outlook. For an overview of qat-files used by Outlook see this post.	*.qat
	Windows XP: C:\Documents and Settings\%username%\Local Settings\Application Data\Microsoft\Office\ Windows Vista: C:\Users\%username%\AppData\Local\Microsoft\Office\
Secure Temp (OLK)	This is the Temp folder for Outlook where it stores files to when they are directly opened from within Outlook instead of being saved to disk first by the user. The folder name is variable and its exact location is exposed in the registry.	any file format
	Windows XP: C:\Documents and Settings\%username%\Local Settings\Application Data\Microsoft\Windows\Temporary Internet Files\<variable>\ Windows Vista: C:\Users\%username%\AppData\Local\Microsoft\Windows\Temporary Internet Files\<variable>\

File Names

<profilename> refers to name of the profile you have configured for Outlook. By default this is either "Outlook" or "Microsoft Outlook Internet Settings".

Name	Description contents and Locations	Migrate?
*.pst	Personal Message Store Main data file for Outlook containing all you Mail, Calendar, Contacts, Tasks, Notes and Journal items. In addition to that it can contain "hidden" data or settings such as Views, Rules, Categories (since Outlook 2007), per folder AutoArchive settings, etc… By default the first pst-file is called outlook.pst. When you have AutoArchive enabled, you’ll have a file called archive.pst as well. If you connect to a SharePoint List, then you’ll also have a file called "SharePoint Lists.pst". IMAP accounts also uses this file format to cache their data in. Additional automatically created pst-files are appended with a number e.g.; outlook0,pst, outlook1.pst, archive0.pst, etc… You can create additional pst-files if you want and can place them in a different location but network locations are not supported. Further information about the pst-file can be found here. Corruption of the main pst-file can prevent Outlook from loading correctly and could also lead to data loss. Therefore you should backup these files on a regular basis.	Possible
	Location: Local Profile Settings
*.ost	Offline Message Store Similar to a pst-file but represents an offline cache of an on-line mailbox intended to enable offline access and to reduce network traffic or to increase Outlook performance when using a slow connection. These files were originally used only to cache an Exchange mailbox but the Outlook Connector also uses this file format to cache Live Hotmail mailboxes. By default the file is called outlook.ost when connecting to Exchange and <Live ID>.ost when created by the Outlook Connector e.g.; yourname_hotmail.ost or yourname_live.ost. Additional automatically created ost-files are appended with a number e.g.; outlook0.ost, outlook1.ost As it is merely a cache and the actual data remains on the server, there is no need to backup this file. When it gets corrupted it can prevent Outlook from loading correctly but as long as you still have access to the Exchange server you can recover by renaming it to .old. Upon deletion (or renaming) it will be automatically recreated when you connect to the mail server again.	Not needed
	Location: Local Profile Settings
*.nst	Notes Message Store Similar to an ost-file but then used for an offline cache for use by Lotus Notes Connector accounts. It may also be used by other connector type accounts. Older versions of the Outlook Connector for instance also have used this file format.	Not needed
	Location: Local Profile Settings
*.pst.tmp	A temporary file indicating a file lock on or queued data to be written to the similarly named pst-file.	Not needed
	Location: Local Profile Settings
*.ost.tmp	A temporary file indicating a file lock on or queued data to be written to the similarly named ost-file.	Not needed
	Location: Local Profile Settings
*.oab	Offline Address Book files for Exchange accounts. It consist out of 6 files all containing different information or indexes about the users in the corporate global address book (GAL). Similar to the ost-file it is designed for offline usage, reducing network traffic and optimizing responsiveness when working on a slow connection.	Not needed
	Location: Local Profile Settings
*.oft	Outlook Form Template Templates and custom forms are stored in the oft-format when saved outside of Outlook. You should make a backup of these files and you can also migrate them for use on another computer.	Possible
	Location: Templates
*.xnk	Exchange Shortcuts These files represent shortcut links to folders accessible within Outlook. They are similar to computer shortcuts (lnk-files) which point to other files on the computer. Since Outlook 2007 the file format is no longer registered for direct execution but that can be enabled again. You can migrate these files to another computer or even share them (when they link to a Public Folder for instance) but of course that location should also be available on the other computer.	Possible
	Location: Folder of choice
*.pab	This is the Personal Address Book file. Previous versions of Outlook allowed you to store your contacts in a pab-file if you didn’t use the Contact folder. The main reason for having a pab-file was that the Contacts folder in Outlook 97/98 didn’t support personal distribution lists. This feature was added in Outlook 2000. In Outlook XP/2002 a pab-file was no longer created or linked by default but could be manually added. Since Outlook 2007 you can only directly import pab-files into your Contacts folder. If you still use pab-files for some reason, you should either back it up or import them into the Contacts folder and stop using them completely.	Possible/ not needed
	Location: Roaming Profile Settings
*.rwz	Outlook Rules Wizard This file format can store your rules that you have configured in Outlook. Since Outlook XP/2002, rules are stored within the mailbox itself instead of a separate file. You can still create a backup of your rules in the rwz-format and import them. You can make a backup of this file for local use when you still use Outlook 2000 or previous but due to in-file dependencies you shouldn’t attempt to migrate this file.	Not possible/ not needed
	Location: Roaming Profile Settings
*.qat	Contains the Quick Access Toolbar (QAT) configuration information. There are up to 19 qat-files for Outlook 2007. For an overview of their naming and which type of window they apply to see this post.	Possible
	Location: Local Profile Settings
*.msg	Outlook uses the msg-format to store messages and other mailbox items outside of Outlook without losing the Outlook interface when you open them from outside of Outlook. Any attachments that the message holds are also contained within this file. This allows you to open individual items on another computer on which Outlook is installed. Note that msg-files created in the Unicode format cannot be opened in Outlook XP/2002 or previous.	Possible
	Location: Folder of Choice
*.htm *.txt *.rtf	Outlook uses these "well known formats" to store the signatures in or to store Outlook messages in a format which can be used by other applications as well. In case of the signatures, additional files and folders can be created in the signatures folder to save formatting information or pictures which have been used in the signature. When saving a message in this format, attachments will not be saved with it.	Possible
	Location: Signatures Location: Folder of choice (when saving messages)
*.mlog	Log file created by the Outlook Connector mainly for use of handling meeting requests correctly. This file is automatically created or recreated when missing upon starting Outlook.	Not needed
	Location: Local Profile Settings
*.otm vbaproject.otm	Outlook VBA Module Contains your configured macros and VBA programs created in the Visual Basic Editor. The default first project is stored in a file vbaproject.otm. If you have any macros configured, it is highly recommended to make a backup of this file or document your code elsewhere. You can also migrate these files to another computer.	Possible
	Location: Roaming Profile Settings
outcmd.dat	Outlook Commands This file contains the command bar and menu customizations that you make in Outlook. is corrupted, it can prevent Outlook from loading correctly. You can make a backup of this file for local use but due to dependencies of installed addins, it is not recommended to migrate this file between computers. It is worth a shot to try it though as in case you run into issues, you simply rename the file to outcmd.old to reset.	Not recommended
	Location: Roaming Profile Settings
extend.dat	This file contains information and settings for registered Exchange Client Extensions (ECE). When it is corrupted, it can prevent Outlook from loading correctly. There is no need to make a backup of this file. Upon deletion it is automatically recreated from registry information. You shouldn’t migrate this file between computers as there is no need to do so since it is recreated from information on the local computer. When migrating, you’ll likely end up corrupting the configuration.	Not needed
	Local: Local Profile Settings
views.dat	Contains view settings for displaying of the folders. This file is used by Outlook XP/2002 and previous and no longer used by later versions of Outlook as since Outlook 2003 this information is contained in the mailbox or pst-file. You can make a backup of this file for local use when you still use Outlook XP/2002 or previous but due to in-file dependencies you shouldn’t attempt to migrate this file.	Not possible
	Location: Roaming Profile Settings
frmcache.dat	Forms Cache A cache file holding information about the cached custom forms in the local Forms folder. If it gets corrupted, custom forms might prevent from loading, display older versions of the form or my cause other unexpected results. Recovering can be achieved by clearing the folder which can be done in several ways.	Not needed
	Location: Forms Local Cache
Normail.dot	Normal.dot is the default file Word 2003 and previous use to store settings such as formatting styles, AutoText, custom toolbars and macros. When you use Word as your email editor, in Outlook 2003 or previous, then this file gets loaded as well. It is also used when you have Word set as your default HTML editor and use the "Advanced Editor" to create a signature. If the normal.dot file gets corrupted or if certain addins or ActiveX components are installed in Word, this will affect Outlook’s behavior as well. Resetting the normal.dot file can be done by renaming it to .old. This file should be backed up if you made custom changes and the file can be migrated between machines although certain addin dependencies can prevent it from working correctly.	Possible
	Location: Templates
NormalEmail.dotm	NormalEmail.dotm is similar to the normal.dot file and has been introduced in Outlook 2007 to support the new email editor and to break the dependencies with Word and to offer Outlook specific support. Quick Parts information is also stored in this file. This file should be backed up if you made custom changes and the file can be migrated between machines.	Possible
	Location: Templates
custom.dic	TThis file contains the words which you add to the dictionary via the spell check options. Since Outlook 2007 it is stored in the Unicode format and its location changed from the Proof folder to the UProof folder. This is a shared file between other Office applications. The file can be edited via the spell check options in the Office applications that use it or directly via Notepad. This file should be backed up if you made custom changes and the file can be migrated between machines.	Possible
	Location: Proof (Outlook 2003 and previous) Location: UProof (Since Outlook 2007)
offitems.log outitems.log	These files contain items that have been added to the Journal or should still be added to the Journal. When all the latest changes have been committed to the mailbox, then you can safely remove these files without losing data. The file outitems.log tracks Outlook items that have been created during the last Outlook session and the file offitems.log tracks documents created by other Office applications which have been committed to Outlook during the last Outlook session or should still be committed when Outlook is closed.	Not needed
	Location: Roaming Profile Settings
RefEdit.exd	A cache of used form controls to speed up inserting the control again at a later time.	Not needed
	Location: Forms Roaming
outlook.box	Contains settings for the custom Toolbox when designing a form.	Not recommended
	Location: Forms Roaming
<profilename>.nk2	Outlook AutoSuggest file (sometimes also named "AutoComplete file" or "nickname cache") This file is used in Outlook 2002/XP, Outlook 2003 and Outlook 2007 to cache up to 1000 addresses that have been used before to address an email, meeting request, task request, etc… This file holds no relation to the Contacts folder and shouldn’t be relied on to securely save contact information as it is only a cache. You should really use the Contacts folder for that. If you like to keep the cached information, you can migrate this file between machines as long as you rename the file after the name of the mail profile and the version of Outlook is the same. However, corruption of the file could break the mail profile or vice versa. In that case the mail profile should be recreated.	Possible
	Location: Roaming Profile Settings
<profilename>.nick	Same as above but then used in Outlook 2000.	Possible
	Location: Roaming Profile Settings
<profilename>.fav	This file is used in Outlook 2002/XP and previous to hold the configured shortcuts (Favorites) in the Outlook Bar for the corresponding mail profile. The Outlook Bar has been replaced by the Navigation Pane in Outlook 2003 and later (see <profilename.xml>).	Possible
	Location: Roaming Profile Settings
<profilename>.srs	This file holds the send/receive settings for the corresponding mail profile. You can make a backup of this file for local use but due to in-file dependencies you shouldn’t attempt to migrate this file.	Not possible
	Location: Roaming Profile Settings
<profilename>.xml	This file holds customization settings for the Navigation Pane in Outlook 2003 and later. Most notable settings are, Favorite Folders, Shortcuts from the Shortcuts Navigation and opened shared folder lists in the Calendar, Contacts, Tasks and Notes and Journal Navigation. A corruption of the file can lead to loss of these configuration settings, being unable to remove certain folders or wrong folders showing up in the described sections. You can make a backup of this file for local use but due to in-file dependencies you shouldn’t attempt to migrate this file.	Not possible
	Location: Roaming Profile Settings
<profilename>.sharing.xml.obi ~last~.sharing.xml.obi	Contains information about the last sync process of (shared) services subscriptions such as RSS feeds, Exchange, SharePoint and Internet Calendar. ~last~.sharing.xml.obi contains the latest sync information of RSS feeds with Internet Explorer (Common Feed List).	Not needed
	Location: Local Profile Settings
<profilename>.xml.klf	Known Feed List. This files contains information about which RSS feeds the specified Outlook mail profile syncs with the Common Feed List feature of Internet Explorer.	Not needed
	Location: Local Profile Settings
OutlPrnt	This file contains the print style settings. When it gets corrupted or if it becomes very large (in general, even with a lot of custom printing styles, this file shouldn’t be larger than a couple of hundred KB in size), you could run into printing errors. Rename it or delete it to recover.	Possible
	Location: Roaming Profile Settings

Registry locations

<version> refers to the version number of Outlook which is installed. An overview can be found here.

Name	Contents and Location	Migrate
Main Outlook settings (user)	Most settings for options you can set in Outlook are saved here. Some keys will refer to folder paths on the local machine or contain other local data such as the machine name. When you filter out these keys, then you can migrate this registry hive to another machine.	Possible (once filtered)
	HKEY_CURRENT_USER\Software\Microsoft\Office\<version>\Outlook\
Generic Office settings (user)	Additional Outlook settings and generic Office settings are stored here. The settings Outlook save here usually depend on components from other or generic Office applications. As long as you heavily filter this registry hive, then you can migrate the remaining settings. Due to the limited amount of valuable Outlook settings which are stored here, it’s not recommended to spend your time migrating this key unless you’ll need it for other Office applications as well.	Possible (once filtered)/ Not recommended
	HKEY_CURRENT_USER\Software\Microsoft\Office\<version>\Common\
Registered addins (user)	Installed addins which allow themselves to be enabled/disabled on a per user basis are exposed here. Since these keys are created when the addins are installed, there is no need to migrate this key.	Not needed
	HKEY_CURRENT_USER\Software\Microsoft\Office\Outlook\AddIns\
Registered Exchange Client Extensions (user)	Sometimes created by mistake on Windows Vista by a custom ECE. This key should be removed then.	Not needed
	HKEY_CURRENT_USER\Software\Microsoft\Office\<version>\Outlook\Exchange Client Extension\
Mail Profile settings	Configured mail profiles are stored here. These keys have a very high interrelation with each other and heavily depend on exact file locations on the local machine. Due to this, small errors in this registry hive could lead to a fully non-functional Outlook until the mail profile is recreated. While you can make a backup of this registry hive for local use, due to the reasons above and because of most settings in this hive are stored in hexadecimal values, it is not recommended to try to migrate the mail profiles to another machine. For this, it is recommended to use a backup application suitable for mail profile migration or manually recreate it.	Not recommended/ Not possible
	HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows Messaging Subsystem\Profiles\ Outlook 97 - 2000 in IMO use: HKEY_CURRENT_USER\Software\Microsoft\Windows Messaging Subsystem\Profiles\
Protected Storage	This key is used by Outlook to store the passwords for mail profiles on Windows XP. Windows Vista and later do not support this old method anymore for read/write use and uses a newer mechanism which is supported by Outlook 2003 and later. Migrating this key is not possible but removing this key can solve account password issues on Windows XP.	Not possible
	Windows XP: HKEY_CURRENT_USER\Software\Microsoft\Protected Storage System Provider\
Last logon settings for Exchange	The last settings used to logon to an Exchange Server are stored here. It is used to pre-fill some dialogs like the username for the login dialog and caches some other settings. There is no need to backup this hive or migrate it to another machine but it can come in handy in certain scenarios to pre-write the LogonDomain and UserName registry key to increase first-use experience for end-users.	Not needed
	HKEY_CURRENT_USER\Software\Microsoft\Exchange\
Main Outlook settings (computer)	System wide Outlook settings are stored here although you are likely to find only component registrations. Since all of the options are system wide, these settings are not directly exposed to the end-user via the Outlook interface so it is very unlikely that any changes have been applied to this hive after installation. Therefore, there is no need to migrate this hive. In case there is a specific need for it, you’ll have to filter the registry hive first from unneeded keys.	Not needed
	32-bit Windows: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\<version>\Outlook\ 64-bit Windows: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Office\<version>\Outlook\
Generic Outlook settings (computer)	This key is similar to the "Main Outlook Settings (computer)" but then for shared Office components. Similar to that hive, you’ll find no need to migrate this.	Not needed
	32-bit Windows: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\Common\ 64-bit Windows: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Office\Common\
Registered addins (computer)	Similar to "Registered Addins (user)" but then for installed addins which allow themselves only to be enabled/disabled on a system wide basis by an administrator. Since these keys are created when the addins are installed, there is no need to migrate this key.	Not needed
	32-bit Windows: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\Outlook\Addins\ 64-bit Windows: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Office\Outlook\Addins\ On a 64-bit Windows version, additional settings can be found in the 32-bit Windows location as well
Form Regions	Similar to the "Registered addins (computer)" but then for Form Regions. Only when you are developing Form regions for yourself and have manually added the keys, then it would be recommended to make a backup of the hive. In all other cases, it will be recreated automatically when you reinstall or reregister the Form Region.	Not needed
	32-bit Windows: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\Outlook\FormRegions\ 64-bit Windows: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Office\Outlook\FormRegions\
Generic properties for Exchange accounts	Several generic Exchange provider settings and options are stored here. Unless you made any explicit changes to it yourself, there is no need to migrate this hive. If you did make changes here, then only migrate the settings that you have actually changed. The hive is small enough to go through it manually.	Not recommended/ Not needed
	32-bit Windows: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Exchange\ 64-bit Windows: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Exchange\
Registered Exchange Client Extensions (computer)	Installed Exchange Client Extensions have made themselves known here to Outlook. As these keys are automatically created by the installed ECE, there is no need to migrate this hive.	Not needed
	32-bit Windows: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Exchange\Client\Extensions\ 64-bit Windows: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Exchange\Client\Extensions\