TypeMock thinks it's not enabled with VS 2008 but it is!

I am using TypeMock v 4.3.1.0 and Visual Studio 2008.

I installed the 32 bit version, and I began using it in some of my unit tests. However, when I try to run the unit tests, TypeMock complains to me saying that TypeMock isn't enabled with VS. Here is the error message I get:

Error Message:
Initialization method Company.App.UnitTest.CollatorTest.MyTestInitialize threw exception. TypeMock.TypeMockException: TypeMock.TypeMockException:
*** Typemock Isolator is not currently enabled.
To enable do one of the following:

* To run Typemock Isolator as part of an automated process you can:
- run tests via TMockRunner.exe command line tool
- use 'TypeMockStart' tasks for MSBuild or NAnt

* To work with Typemock Isolator inside Visual Studio.NET:
set Tools->Enable Typemock Isolator from within Visual Studio

For more information consult the documentation (see 'Running' topic).


However, I checked the Tools menu and it says "Disable TypeMock Isolator", so I'm assuming that means that TypeMock is enabled on VS. I try to disable TypeMock integration, run the test, I get the same error. When I enable TypeMock integration, run the test, I get the same error. I'm not sure what's going on or how to resolve this issue.