It sort of makes sense as the oldest tmp file corresponds to the oldest backup. I agree that it is not good design. I don't fancy a BSOD just at the moment as about to go away on holiday so need to have the server working reliably while I am away or I get no email Could be one for the MVP's to feed back into Microsoft for a comment.
Thank you for confirming that Dave! I don't have the full gui installed so I couldn't do a Disk Cleanup on mine. I wondered if that would work to get rid of them. Guess not. I suspect they may be some kind of mount point for the vhd that is created right at the beginning of backup and deleting them causes havoc later when Server Backup tries to do incremental backups using the old mount point. My backups "exist" forever since they are on 1TB and in no danger of running out of space. It occurred to me that maybe they get deleted when a backup gets removed. In any case it's a pretty piss poor design to leave critical ".tmp" files in Windows\Temp if you ask me. If you really want to test things at your end, delete them In any case at least I know what has been causing the random BSODs I get every few months since I installed WSE2012 and what to do not to get them.
Sorry, the backups are not compatible with WHS 2011 or any of the Server Essentials variants. There is no easy workaround either. You don't give any indication in the spec of the V1 box so difficult to say whether Essentials will run on it. I beleive the limitation may possibly be RAM if you are thinking of one of the original HP Home Servers.
So I have a new WSS box arriving tomorrow. Are the backups made with V1 compatible with Essentials? Is it possible to migrate them to the new box? Any suggestions on what to do with the V1 box? It it possible to load Essentials on it (legality aside)?
Curious, I have just checked on my 2012E (not R2) and I also have a load of tmp files in C:\Windows\Temp. This is clearly a side effect of the Essentials server backup and I currently have 800 of them. The only space they will be taking up is slots in the directory files and so there is no danger of running out of disk space. I am going to see if Disk Cleanup will tidy them up without messing up the server. EDIT: Disk Cleanup doesn't seem to touch them - they are still there.