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what is the extend.dat file used for?

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cmc1228

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Jul 28, 2009, 12:11:01 PM7/28/09
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To find problematic user data in the windows profile it was advised to rename
and/or delete the extend.dat, frmcache.dat, outcmd.dat, and olk*.qat files.
What specifically do each of these files do and what is actually being
deleted when resetting these files?

Brian Tillman [MVP - Outlook]

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Jul 28, 2009, 2:34:51 PM7/28/09
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"cmc1228" <cmc...@discussions.microsoft.com> wrote in message
news:962A6E4A-CA6E-42DA...@microsoft.com...

See this for a brief explanation of these files:
http://www.slipstick.com/config/backup.asp
--
Brian Tillman [MVP-Outlook]

cmc1228

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Jul 28, 2009, 2:49:01 PM7/28/09
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Is this a non-destructive way to troubleshoot Outlook crashes/performance
issues without having to recreate a new profile? Looks like the only data
that would be lost after resetting these files are pointer to add-ins,
customized toolbar settings, and custom form settings. Is that correct?

Also will this work on both outlook 2003 and 2007 given their respective
file locations?

Thank you for replying.

Brian Tillman [MVP - Outlook]

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Jul 28, 2009, 3:36:44 PM7/28/09
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"cmc1228" <cmc...@discussions.microsoft.com> wrote in message
news:61376B04-1CCC-4EAA...@microsoft.com...

> Is this a non-destructive way to troubleshoot Outlook crashes/performance
> issues without having to recreate a new profile? Looks like the only data
> that would be lost after resetting these files are pointer to add-ins,
> customized toolbar settings, and custom form settings. Is that correct?

Deleting those files and allowing Outlook to recreate them isn't quite the
same as a new mail profile. To recreate some of those files, Outlook rereads
the registry. if the problem is in a registry setting, then recreating those
files will simply create them again with the problem, but most of the time for
some problem it can be quite helpful without having to recreate the profile.
Even so, though, recreating the profile is hardly difficult.

> Also will this work on both outlook 2003 and 2007 given their respective
> file locations?

Yes. There's a link on the page I ceited that directs you to a page giving
the Outlook 2007 file descriptions and paths.
--
Brian Tillman [MVP-Outlook]

cmc1228

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Jul 28, 2009, 6:38:01 PM7/28/09
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do you have specific examples of how resetting those files would help over
just recreating a new profile?

"Brian Tillman [MVP - Outlook]" wrote:

Brian Tillman [MVP - Outlook]

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Jul 29, 2009, 8:22:23 AM7/29/09
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"cmc1228" <cmc...@discussions.microsoft.com> wrote in message
news:51844CF3-3914-471E...@microsoft.com...

> do you have specific examples of how resetting those files would help over
> just recreating a new profile?

Here are two: the first is if the Outlook window itself is having problems and
buttons or menus are missing. Deleting the outcmd.dat file will help with
that. The second is if, when you start Outlook and receive a message that
there is a missing add-in and you should run Detect and Repair, but the add-in
is, say, an antivirus scanner that you deleted. Deleting the extend.dat file
should help with that.
--
Brian Tillman [MVP-Outlook]

rbie...@gmail.com

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Oct 29, 2016, 4:48:56 PM10/29/16
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This is an old post but i am hoping someone out there stumbles upon this shortly.

Office 2007 opens up and after loading stops working.
CPU is at 100% so it's hard to do anything, i have stopped all major processes and there are no malware or viruses.

Will deleting the extend.dat help?
or
Program files right click change and repair 2007 office?
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