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Using Microsoft Outlook 2010 on a network with a Microsoft Exchange Server 2010. The Exchange Server is the only email address associated with my Outlook. Have not had any problems for over a year, but three days ago my email cache disappeared.

In other words, when I start typing an email address to send a new message, my previously sent email addresses do not list. They will start to re-accumulate all day while I use it, but will be gone again after a reboot.

Has anyone else had this problem?

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Check when it's the last modify date for Outlook.nk2. That file is keeping all the "auto-populated" email addresses int he "TO:" field. It will be in there: C:\Documents and Settings\Username\Application Data\Microsoft\Outlook – r0ca Jan 12 '12 at 15:29
Do you know if the user has a roaming profile? – r0ca Jan 12 '12 at 15:44
Outlook 2010 does not use .nk2 files. – thims Jan 12 '12 at 15:58
Not using a roaming profile and the rest of his profile seems normal and intact – James Watt Jan 12 '12 at 16:10
up vote 1 down vote accepted

This can be caused by a corrupted Autocomplete list (what used to be the .NK2 files, now C:\Users\%username%\AppData\Local\Microsoft\Outlook\RoamCache\Stream_Autocomplete*.dat.), so try flushing it and see if that helps:

In Outlook 2010:

  • File -> Settings -> Mail -> Send Messages -> Empty Auto Complete List
  • Restart Outlook.

Or run Outlook 2010 with the CleanAutoCompleteCache switch:

Outlook.exe /CleanAutoCompleteCache

Hopefully that'll make it remember better. ;)

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All of the .dat files must have been corrupted because they all were dated 11/16/2011. I cleared them out, started Outlook with /CleanAutoCompleteCache and everything worked fine. .dat files are now reporting today's date. Thanks! – James Watt Jan 18 '12 at 16:53

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