Cannot debug Unit Tests

I have VS2008 Team Ed. for Testers.  I was successfully debugging unit tests earlier today, but now I can't.  I select Test -> Debug -> Tests in Current Context.  Then:

The Visual Studio development Web server starts (is that normal?)

The test runs, but break points are not hit.

Restarting VS2008 didn't help.


It may have started when this happened to me:

I was stepping through a unit test.
I edited the unit test and tried to use the "edit and continue" feature.
VS2008 said I could not do that and must restart.
I told it to restart.
Instead of re-running (and debugging) the unit tests, it tried to run my web app.
I stopped the web app.

Now I can't debug unit tests.

Is there something I can clear or reset?

Chris