We have just recently installed Office 2013 Professional Plus 64bit on three machines {Windows 7 Professional 64bit SP1} in preparation for deployment.  On two out of three of them, when in cached mode, we continually receive the message upon starting Outlook "Preparing for first use". Also, multiple .ost files are being generated approximately every hour or so. This renders the machines almost unusable.  When we take Outlook out of cache mode, everything is fine and all other Office applications are fine.  We have tried deleting all of the .ost files and the mail profiles, we have tried "Run As Administrator" and starting Outlook in Safe Mode.  None of these things has helped.  We are pretty much out of ideas and would appreciate any and all ideas, suggestions, and help in general.

Thank you ...

Hi,

Do you have a Roaming Profile or Folder Redirection environment? Outlook will try to create a new OST file if the old OST file cannot be found due to something changing in the folder redirect, or the roaming profile coming back down without the OST or a new temporary local profile is created.

Do you create backups of the OST file at regular intervals or have some backup software installed which does it automatically? This may also cause this issue.

In addition, do you happen to use a PRF file to set up your mail profile? If so, please double click to open the PRF file and make sure you can see the lines below in it:

BackupProfile=No

OverwriteProfile=No

Please let me know the result.

Regards,

Steve Fan

Forum Support