Too many variables to lock it down with the information you've provided however. Are you running exchange over http? Perhaps when your laptops are out they're getting a copy that is either opened or viewed and then when they are connected to the domain it generates an error. I would make changes to one controlled Outlook instance, clear the sync folder, turn off cached exchange mode and see what you get. I have turned off cached exchange mode on all my domain workstations that are not mobile as there is no real reason to run it (our servers have a very high up-time). Also - I don't think that sync errors can occur if you are not running in cached Exchange mode as there is nothing to sync to (thus the reason for being out of sync). On that, is there a pattern of when and to whom the sync issues happen, or does it just seem to occur randomly throughout the day. This might even alleviate some of the sync issues you're having, although I think that is perhaps a different issue. If you've recently been running out of space and you've created more, it might be a good idea to run an offline defrag of your Exchange DBs. A restart of the exchange services would rectify it temporarily, and a reboot of the server took care of it a little linger, but it wasn't until a day or so after this started and I migrated the DB to the SAN drive as originally planned did the whole thing clear up.

This started causing all sorts of havoc with mail not getting sent properly and the server not accepting new mail. Well before I migrated the DB over at one point the server C drive was down to <5GB, but I still had space though only a little space. In my initial setup due to various reasons I had the exchange DB on the C drive of the SBS box, and the original plan was to have it on the SAN.

I recently migrated to SBS 08 and I had also purchased another server which I setup as a homegrown SAN with openfiler. From my experience they are not because it has happened even with a small amount of space left of the server. I was simply asking if anyone has had the same problem before and if the two were directly linked. It is common knowledge that if a hard drive is full you should probably delete a few things to give your self some space.

Of course I did not leave the exchange server full.

How do i find outlook 2016 sync issues