Moving this discussion to the Installing Flash Player forum.
Please press Ctrl, Alt, Delete keys together. Go to Task Manager and select the Process tab. Verify if you see a process named GPlyer.exe. If you see, select it and click End Process.
In the following page, you have step-by-step information: http://helpx.adobe.com/x-productkb/global/error-close-following-applications-continue.html