addmonitor fails on vista 64

Question

I have made an application that adds a port monitor using the addmonitor windows function. It runs fine on Windows XP. On Vista Ultimate 64 I manually copy the port monitor dll to c:\windows\system32, when I try to execute the application as administrator the addmonitor function returns FALSE. Any idea what is wrong?

 

The application is as follows:

 

int _tmain(int argc, _TCHAR* argv[])

{

MONITOR_INFO_2 mi;

mi.pName = _T("Test Port");

mi.pEnvironment = _T("Windows NT x86");//NULL;

mi.pDLLName = _T("testport.dll");

 

BOOL rc  = AddMonitor(NULL, 2, (LPBYTE)&mi); // this fails for Windows Vista, but works on Windows XP

if (rc)

{

::AddPort(NULL, NULL, _T("Test Port"));

}

 

return 0;

}

Answer 1

Couple of things. Use GetLastError to find out what the actual failure value is.

 

I note that your environment is set to Windows NT x86, shouldn't it be Windows x64.

Answer 2

I retried with the environment set to "Windows x64". GetLastError() returns error 193, ERROR_BAD_EXE_FORMAT.

 

The application is build on a 32-bit Windows XP system. Isn't the WOW64 emulator able to run this application?

 

In that case I would have to build one 32-bit and one 64-bit version of the setup application, and let an installer determine the if the platform is 32 or 64-bit and run the corresponding application. 

Answer 3

The testport.dll port monitor is also build on a 32-bit system. I guess the print spooler on a 64-bit system will be unable to load a 32-bit dll; I would have to build a 32-bit and 64-bit version of the dll and let a installer decide which dll to install on a system. 

Answer 4

 

I would install the 64 bit version on a 64 bit box.