Problem with mutex

[Artem Moroz]

I have a problem with named mutex. In my 1st process I am creating mutex CreateMutex(NULL,TRUE,"Process_Running"); // mutex will be automatically deleted when process ends. if(GetLastError() == ERROR_ALREADY_EXISTS) { AfxMessageBox(IDS_ALREADYRUN); } Then, in 2nd process I am try to determine, whether 1st process is running: HANDLE hMutex = OpenMutex(0,FALSE,"Process_Running"); if (hMutex != NULL) { CloseHandle(hMutex); // Do something... } But in this code hMutex is always NULL ! Even if 1st process is running! What am I doing wrong ?

[John M Drescher]

It looks like you want to limit your application to single instance. Here is some code for that: http://www.codeproject.com/cpp/csingleinst.asp[^] http://www.codeproject.com/useritems/single_instance_checker.asp[^] John

[Michael Dunn]

The first param to OpenMutex() should be MUTEX_ALL_ACCESS. --Mike-- Ericahist | Homepage | RightClick-Encrypt | 1ClickPicGrabber Latest art~!@#2rDFA#@(#*%$Rfa39f3fqwf--= NO CARRIER

[Artem Moroz]

It works! Thank you for help ! ;)