Occasional error on Partial Class name and inherits ???

I get this error every so often, and can usually get around it by doing a few refreshes or sometimes navigating away from my site then back to it: 

Compilation Error




Description: An
error occurred during the compilation of a resource required to service
this request. Please review the following specific error details and
modify your source code appropriately.



Compiler Error Message: ASPNET:
Make sure that the class defined in this code file matches the
'inherits' attribute, and that it extends the correct base class (e.g.
Page or UserControl).


Source Error:







...