Outlook File Extension Question

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Hello All,

Looking at a full hard drive issue I noticed that the outlook folder was extremely large (108GB+), when I opened it I noticed the pst files and the normal outlook files, but there are 18 files that look like the following;


SBSE___.7LD 11/15/2013 9,091,449 KB

SBSE___.7P7 5/25/2013 3,138,953 KB

SBSE___.9QC 3/28/2013 8,147,313 KB

SBSE___.38C 6/14/2013 8,488,809 KB

SBSE___.43C 7/8/2013 3,359,921 KB



This goes on for 18 different files, when I googled the extensions, they say they are unknown file extensions. This account uses IMAP, are these something to do with the folders he created in outlook? Do you think I am safe to delete them?

Also, we use a program called SyncbackSE to backup all of the files, and they are bringing over everything but these 18 files, they will not transfer, almost like it doesn't even know they are there, and these are not hidden files.

Any ideas what they are and if I can delete them?


You mentioning SyncbackSE made me wonder if SBSE would be related to SynBackSE. The weired extensions looked like temporary files to me.

Google(d) syncback temporary files and found e.g.http://www.2brightsparks.com/bb/viewtopic.php?t=7867 confirming my idea.

Since this has nothing to do with outlook, I wonder if anyone in this forum can help you..

Its the backup creating them -it can't correctly backup outlook files in use and creates a temp while it waits for outlook to close. Since you are using imap, you don't need to backup the imap folders, but do need to back up the calendar/contacts PST. I'd move it to the documents folder and configure the backup to skip the folder under your user account/local appdata.

Delete the older files but I'd keep the newest.
Btw, you'll still get these files if you don't occasionally close outlook, but they should be smaller if they are only for calendar and contacts.
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