什么原因导致“内部连接致命错误”

I've got a number of ASP.Net websites (.Net v3.5) running on a server with a SQL 2000 database backend. For several months, I've been receiving seemingly random InvalidOperationExceptions with the message "Internal connection fatal error". Sometimes there's a few days in between, while other times there are multiple errors per day.I've got a number of ASP.Net websites (.Net v3.