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Thank you for your question. I will do my best to assist you. My name is Jamie.
1. Hold Ctrl+Shift and press Esc.
2. Locate “Windows Explorer” under “Windows processes”, now right click on it and click “End task”.
3. Now click on “File” at the top of the window and click “Run new task”.
4. Type “explorer.exe” without the quotes and tick the box labelled “Create this task with administrative privileges” and click “OK”.
Let me know if that doesn't work.
Also be sure the security permissions on the C:\Windows\Installer directory. This is a hidden system folder, so you may have to change your Windows Explorer view options to be able to see it (Organize > Folder and search options > View tab).
The permissions required on the folder are as follows: