I get timeout errors every couple of days or so between IIS7 and an SQL 2008 Server. The error message I get is:
System.InvalidOperationException: Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached.
Sometimes this sorts itself out, other times I need to manually restart SQL Server. Is there any way I can trace down the cause of this error. I'm 90% sure it's somewhere without our ASP.NET webforms app where a connection is being opened and not closed, but I'm at a loss to pin down the cause.