Returns the last error code that has occurred in the system. This method helps to debug programs. If the error number is a positive number then it is based on the MSDN GetLastError values and you can use the FormatMessage function of the Microsoft API to return a text string description of the error.
If the error returned is -1000 then the DEVMODE value was NULL.
long BlackIceGetLastError();
Return value - The error code.