P6.7 SP2 External Exception Error Message Keeps coming up stopping all works in P6, Event Code: EEC-

Subject: P6.7 SP2 External Exception Error Message Keeps coming up stopping all works in P6, Event Code: EEC-2521-2

Hello there,

Does anyone in the Primavera community knows what the above Event Code error means?  Its an external exception that our IT people cannot identify nor fix  yet.  If you know what this is, can you please suggest a fix. 

Our present s setup:

P6 Version 7 SP2

Concurrent access through Citrix

140 Active Users

I cannot find any write up or troubleshooting-solution guide  in the knowledge base.  If you have some document you can share regarding this problem, you can even send it to me directly to