Curious, How big is the database?

After open lots of objects in design mode the database can bloat significantly. If it get to the 2 gig limit you will have all kinds of issues. It is common to have database corruption when this happens.

If the database if very large even after compacting then you will have to be very careful and watch the file size..

__________________
Boyd Trimmell aka HiTechCoach (.com)
Microsoft Access MVP Alumni 2010-2015

Is it the case that many tables in the Access database are actually linked external references (e.g. dBASE or Excel)? Another possibility is that several users have the database open at the same time. For both cases you can solve the problem by making a simple change in the registry.

Open the program regedit.exe (using Start->Run) and navigate through HKEY_LOCAL_MACHINE to

SOFTWARE\Microsoft\Jet\4.0\Engines\Jet 4.0

Increase the value here for the entry MaxLocksPerFile to a number that is twice or three times (maybe even more) the current value.

For further information regarding this, just check out the following link:

http://www.accessrepairnrecovery.com...exceeded-error