Important: This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756How to back up and restore the registry in Windows
To resolve this problem, follow the steps listed below in deleting specific registry keys and values, as well as files related to the Media Center Extender.
1. Log onto the system with an Administrative User Account.
2. Click Start, type Regedit in the Start search box, and then press Enter.
3. Locate and then click the following registry subkey below.
Please note that the “Update media permissions for … subkey will be different that the one listed below.
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Schedule\TaskCache\Tree\Microsoft\Windows\Media Center\Extender\Update media permissions for Mcx1-HTPC
Make a note of the GUID listed for ID. This is the task ID number associated with the Media Center Extender task which you will need to delete later. Please note that your GUID may be different that the one listed in the image below.
4. Now expand to and select the following registry key listed below. Then right-click on the key labeled Extender and choose Delete.
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Schedule\TaskCache\Tree\Microsoft\Windows\Media Center\Extender
5. Expand to and select the registry key listed below. Then right-click on the key labeled with the GUID noted in steps #3 above and choose Delete.
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Schedule\TaskCache\Plain\{5118E7E2-C385-48C0-9A86-DFEE600F1F55}
6. Expand to and select the registry key listed below. Then right-click on the key labeled with the GUID noted in step #3 above.
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Schedule\TaskCache\Tasks\{5118E7E2-C385-48C0-9A86-DFEE600F1F55}
7. Once you have completed the above steps, close the Registry Editor.
8. Open Windows Explorer from the Programs menu and navigate to the folder which contains the scheduled task xml file for the Extender task. For example, if Windows is installed to your C: drive the path would be:
“C:\Windows\System32\Tasks\Microsoft\Windows\Media Center\Extender”
9. Locate and delete the file labeled "Update media permissions for Mcx1-HTPC" which was located in the directory. DO NOT delete the directory. Please note that the file name for the task may be different that the one listed in the image below.
10. Once you have completed these steps close all open applications and reboot the client system. Log onto the system normally and the Task Scheduler should launch without error.