How do I test if another installation is already in progress?

Question

Assuming I\'m trying to automate the installation of something on windows and I want to try to test whether another installation is in progress before attempting install. I

Answer 1

I was getting an unhandled exception using the code above. I cross referenced this article witt this one

Here's my updated code:

  /// 

/// Wait (up to a timeout) for the MSI installer service to become free.
/// 
/// 
/// Returns true for a successful wait, when the installer service has become free.
/// Returns false when waiting for the installer service has exceeded the timeout.
/// 
public static bool IsMsiExecFree(TimeSpan maxWaitTime)
{
    // The _MSIExecute mutex is used by the MSI installer service to serialize installations
    // and prevent multiple MSI based installations happening at the same time.
    // For more info: http://msdn.microsoft.com/en-us/library/aa372909(VS.85).aspx
    const string installerServiceMutexName = "Global\\_MSIExecute";
    Mutex MSIExecuteMutex = null;
    var isMsiExecFree = false;
    try
    {
            MSIExecuteMutex = Mutex.OpenExisting(installerServiceMutexName,
                            System.Security.AccessControl.MutexRights.Synchronize);
            isMsiExecFree = MSIExecuteMutex.WaitOne(maxWaitTime, false);
    }
        catch (WaitHandleCannotBeOpenedException)
        {
            // Mutex doesn't exist, do nothing
            isMsiExecFree = true;
        }
        catch (ObjectDisposedException)
        {
            // Mutex was disposed between opening it and attempting to wait on it, do nothing
            isMsiExecFree = true;
        }
        finally
        {
            if(MSIExecuteMutex != null && isMsiExecFree)
            MSIExecuteMutex.ReleaseMutex();
        }
    return isMsiExecFree;

}