Maybe one of you has seen this. Our "disaster recovery" mail server was upgraded from Exchange 2003 SP1 to SP2 in mid-January. It contains about 10 to 15 mailboxes and I wanted to "test" SP2 on that server before deploying it here. Our main mail server is still running Exchange 2003 SP1 (on Win2000). Since I put SP2 on the Disaster Recovery mail server, I have seen the following error Four times: Error in C++ runtime library..... (in a pop-up window) This occurs on our main mail server. After I see that error, then every 30 seconds I see in the Event Viewer: ID=7011; Source = Service Control Manager Timeout (300000 miliseconds) waiting for a transaction response from the IISADMIN service. And: ID=7011; Source = Service Control Manager Timeout (300000 miliseconds) waiting for a transaction response from the IISADMIN service. Now I'll state the obvious- after that the Info Store is still available and people can read messages, but no new messages are coming in. At that point I either restart IIS or shutdown the server completely. [I think that on the occaisions I tried to just restart IIS, the SMTP Service would not start.] Initially I thought that this was due to either "Symantec Mail Security 4.6" which is running on the server, or maybe "iHateSpam server edition". However, I then realized that it was only 8 hours or so after I had installed SP2 on the other mail server that this started to happen. By the way, these are NOT Front-end/back end servers. Each receives mail on its own, but they are in the same Administrative Group. [We only have 1 administrative group.] I will be applying SP2 to the server with the trouble this Sunday or Monday. In the meantime I wanted to see if anyone was aware of this -- or maybe tell me if I am barking up the wrong tree. Thanks for any tips!!!!