So after much forehead-flattening headbanging, I finally found out why I was getting this infuriating error message in my ASP.NET application.

“Failed to start monitoring changes to {directory name}”

Apparently, when you host a lot of ASP.NET applications using a UNC path for a remote directory where all the applications are stored, the Win32 API gods (demons?) frown on you.

There is a limitation with CIFS and the ReadDirectoryChangesW method.

Thanks to JohnnyLambada!

http://johnnylambada.blogspot.com/2005/05/cachedependency-limitation-as-of-asp.html