Endpoint Protection

I recently built a new Symantec Endpoint Protection Management server (Win 2K8r2) with SEPM version 12.1.6.  My network does not have internet connectivity, so I have been copying the .jdb file into the proper location:  C:\Program Files (x86) - Symantec - Symantec Endpoint Protection Manager - data - inbox - content - incoming.  For the first several times I did this, everything worked perfectly.  Now, my .jdb file acts like it's going to process and then turns into a .jdb.err file.  I have read many blogs with many potential solutions - most of which I've tried with no success.  I have used different .jdb files, stopped and restarted services, recycled server, etc.  I am not sure what to try next.  Any assistance would be GREATLY appreciated.  Thanks.

When did this start? Can you run the symhelp tool on it to do error checking?

Was there an associated log file with that you can post for review?

I have never run SymHelp before but I am downloading it now.  In reading some posts on other threads, it indicates that it will not work on a system with no internet connectivity.

I installed v12.1.6 on June 30th, and the .jdb file worked fine on July 1, July 2, and July 6, but hasn't worked since - and I've tried 4 additional .jdb files since then.