When using IIS and ASP, you can get an IIS error, "Server Too Busy", when ASP executes too many Server.CreateObject requests. Each CreateObject request is queued, waiting until it is its turn to be created. If your queue is set to a max size of 500, when there are 499 items in the queue, the 500th requestee will get a Server too Busy error.
There are steps you can take to solve this problem. An exhaustive discussion of this topic can be found at the following URL: