Process.Start executing old version of my EXE

[google]

Hi everyone,

From my WinForms app I am executing an external process. It turns out

that I have replaced the EXE of the external process with a newer
version and my WinForms app is still executing the old one. I am using
Visual Studio 2005 and programming in C#.

I have been wrecking my brains for two days and I can't find a possible
explanation. These are the things I have tried so far:
-Renaming the new EXE and, of course, referencing the new name in my
code.
-Deleted all the MUICache entries in the registry.
-Removed the EXE completely from my Visual Studio solution and added it
again.
-Deleted all the suspicious caching files of Visual Studio.
-If I xcopy my app to another computer it works.
-If I xcopy my app to another folder in the same dev computer it works
only once; in subsequent runs the old version of the EXE is called
(even with a different EXE name).

This is absolutely frustrating.

I would appreciate any input.

Thanks much!