Connection problem different errors .net application
I think you may be experiencing TCP Port Exhaustion on the Web Server. Avoiding TCP/IP Port Exhaustion is a good starting place for understanding the issue. This is generally an application design/implementation issue.

https://msdn.microsoft.com/en-us/library/aa560610%28v=bts.20%29.aspx?f=255&amp;MSPPError=-2147217396