DLL Conflict

        Hi All,
        I have two web services DLLs installed under IIS
localhost\calcServices\bin\CalcServices.dll localhost\calcServices\bin\CalculatorServices.dll Whenever, I rename one of the DLLs, the other stops working. I know of no dependency between the DLLS.  If I remove one of them, the other works perfectly well.  And with the default names both works fine.
I have one web.config file in ?localhost\calcServices\? Anyone know of any reason for this issue.
FYI: First DLL was created by Visual Studio and the other one was created by Delphi.
What could be the reason for stopping a web service when other DLL in the bin folder is renamed?
Thanks in advance
Biju
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