Problem with Reporting Services

I have an odd problem when I was using Reporting Services.
I have the latest TypeMock 4.0.3.0 evaluation installed and the evaluation period is not over yet.
My computer is installed with VS 1.1.
Before installing TypeMock, I was creating Reports and previewing the reports without any problems.
After installing TypeMock, I could no longer preview and kept getting the error message
"An unexpected error occurred while compiling expressions. Native compiler return value: ‘2000’."
This happened no matter which report I was editing.
Rebooting the computer did not help but by disabling TypeMock in the VS.net Tools drop-down menu, I was able to get my reports to work again. I got the same error when I enabled TypeMock again.
Any ideas? Thanks.