We help IT Professionals succeed at work.

Sync Issues with Outlook 2013

M SOS asked
I have a user who uses Outlook 2013 to connect to Exchange 2010 over a high speed link. I got a call from him saying that all the emails he receives go directly to the Sync folder and they are all coming from one person and only one person. Nothing in his inbox.

I suspected that the issue could be a corrupt .ost file (32 GB in size) so I cleared the Exchange Cache and all worked fine.

Today I ticked this Exchange Cache back again and I could see that the folders where updating ( took a while about 10 minutes) and then with this box ticked everything works fine again.

The user has many mailboxes for other users in his outlook along with many other calendars.

The link speed is really high and that should not be an issue.

What could be the issue?

Help Please

Many Thanks
Watch Question

MacleanSystem Engineer
Well, sounds like you gave the answer yourself. The OST got cleared and re-downloaded which fixed the problem.
So potentially (likely) a corrupt OST.
Or does he have the issue again?


I did not create new profile thought

it was the same profile I just un ticked this cache mode left for a day and then ticked it again

Also the user wants to know why it was corrupted in the first place. Does the file of the OST over 32 GB has anything to do with it?
MacleanSystem Engineer
I would usually remove the cache mode, and rename the old OST.
That way when ticking cache again, it will create a new clean OST without any issues.

The OST size can be pretty much anything in size, as long as your hardware can keep up with the load.
On old SATA 5400rpm drives this would possibly be an issue

As for actual cause there are many possibilities.
His OST might have corrupted during an unexpected system reboot, Outlook hanging/crashing, or having multiple cached files from multiple accounts on a slow hard drive (SSD usually fixes that bit)

You would need to check the event logs for hints, but there is a reasonable chance that these logs have been overwritten by now.

EDIT: Found a article on PST & OST which has some suggestions that might provide you some more insight to OST performance



OK Thanks

So if the OST was corrupt and I removed the Exchanged Cache mode and then leave if for a day and then tick back on again (same profile, same ost file location) fixed the OST file on the local machine? Is that possible?  

Could be a syncing issue?
System Engineer
It might be possible that his hard drive had not updated the OST cache properly, and unticking/reselecting it might possibly have re-initiated the sync fixing the problem.

Reason for it not syncing might have been a lot of hard drive read writes during for example a scheduled AV scan while lots of work was open, which is pretty common.

Have a look at his resource manager from task manager, and see what the load is on his hard drive when a scan runs, while he has his mail and work open. You might see that he has a lot of writes and reads slowing down PC, using more memory, and even going into page file. His blue bar in the graph could be flat-lining at the top during busy periods, causing a problem syncing the OST.

Besides virus scans there might have been daytime patches which were being pushed out by your update management system or automated updates on the computer if unmanaged, This all uses resources