Andrej,
Welcome back
> errors when compile
What errors are them ?
> Can I check in any way that UdlTags.exe is already run
You may use GetModuleHandle():
http://msdn.microsoft.com/en-us/library/ms683199(VS.85).aspx
> or can I kill running UdlTags.exe ?
Once you have the HMODULE using GetModuleHandle(), or you can get it from the window title, then you may call TerminateProcess():
viewtopic.php?f=3&t=13769
This may help also:
http://support.microsoft.com/kb/178893