I have the same problem reported here : http://forums.autodesk.com/t5/AutoCAD-2010/AutoCAD
Fresh installation of Windows Small Business 2011 standard
Disabled offline and cache on shared directories
Removed the router (server and computers in "standalone", just joined by a gigabit switch 5 ports, 2m of cables between the compure and the server)
Installed latest evaluation of Autocad LT 2013
No Antivirus; firewall settings by default
The user is the only one who access to the autocad files.
Still the problem.
The user does want work on the network anymore unless the problem is solved, which is annoying because only the server has a backup routine.
I discovered that the problem is reported long time ago: it really sucks!
I have been looking at this for a while now and thought I would reply with info rather than a solution. (i wish)
We have had a number of users that are ex
periencing this, they either get an ATMP error if they are running BAK files or the get an SAV error if the BAK file is switched off. (we have even said that they dont get an error and that files disapear).
Regarding the SAV error, I am able to re create this error by logging into two accounts and using account A to open an existing drawing from the network. Then Looking at User B and opening same Drawing. User B is presented with a This file can be opend as READ ONLY. and waits for the user to either select yes or no.
If I try to save onuser A's machine, then select yes to READ only on USER B's machine as User B loads the read only copy. user A's request to save, is interrupted and the error "user cant SAVE" occurs.
still banging on with this but thought Ild share incase someone else sees this and decides to try the same test. the more working on it the better is say.
not sure if thjis is worth a read but I feel this has something to do with it. Microsoft have introduced LEASE locking on files rather than the old OPLOCKS.
machines are windows 7 sp1 and data is held Centrally.
hope someone can make a breakthrough soon BAIN of my life/