The error message reads:
Nothing special in the dbmon output.Debug Assertion Failed!
Program: D:\tools\xplorer2.exe
File: c:\windows\profiles\nikos\my documents\c++\kenny\singleinstance.h
Line: 125
Expression: pData && (wcslen((LPCWSTR)pData->lpData)+1)*sizeof(WCHAR) == (int)pData->cbData
For information on how your program can cause an assertion failure, see the Visual C++ documentation on asserts.
(Press Retry to debug the application)
As you can tell from the message above, it only occurs on the second instance.
When I choose 'Ignore' , x2 window shows up and seems run smoothly.