Unless I missed it, you haven't mentioned running any antivirus software or similar. Please disable these.
Are you using encryption software like Bitlocker or TrueCrypt?
What is UAC (User Account Control) set to? Go to Control Panel\User Accounts and Family Safety\User Accounts and choose Change User Account Control settings. Disable it entirely (drag the slider down) for the purpose of this.
Once again, I know its been mentioned before but this step is important:
-check your Account from Computer Management (right click 'My Computer', choose Manage). Don't trust Control Panel/User Account/Account type (I'm sure its oke but just to be sure).
- Open Local Users and Groups, select Users and open properties on your Account Name. Check the Members of and make sure Administrators is listed. If not, add it and Logout and Login again.
Disable any antivirus/antimalware/spyware/related software.
Do an uninstall of MC, reboot.
After the reboot, disable any antivirus/antimalware/spyware/related software again.
Check if the following folders exist and delete them:
- C:\program files (x86)\J River
- C:\Users\AccountName\AppData\Roaming\J River
If you are getting errors about files or folders that can't be deleted, it means ownership is not set to administrators on some of them. Being an Administrator and having Full control will not solve that, we need to take Ownership.
You need to right click the "Program Files (x86)" folder, Choose Properties
Open security tab
Click Advanced
Select Owner tab
Click Edit (even if it shows Administrators in Current Owner!)
Select Administrators
Tick 'Replace owner on subcontainers and objects'
Click OK
Close all dialog boxes
Repeat for the "Roaming" folder
and try deleting the "J River" folders again.
Try a reinstall. If that still fails, try installing MC to another drive or another folder entirely, like "C:\Users\Public\J River". Another drive like D: would be better though.
You can also check your eventlogs from Start/Run type 'eventvwr' and see if there are any warnings or errors around the times you attempted an install or uninstall.