>>My whole class is static.
>
>Do you see any problem I have a local declaration on the lock object?
>
>BTW, I do not know if that is related but I am having a problem with some event being logged in the event viewer with this new architecture.
>
>Application: w3wp.exe
>Framework Version: v4.0.30319
>Description: The process was terminated due to stack overflow.
>
>So, when this happens, the application will restart and I then have a bunch of errors.

I might not have seen enough of your code, but how will other instances know about the lFirstHit variable? I created my class and variable as static so it's a singleton throughout the application.