If you are unable to change the folder permission on your Plesk control panel, try the below steps.
An error message that could probably be displayed is : FileList::init() failed: ls_dir_wrapper() failed: Unable to get file (C:\inetpub\vhosts\domainname.com) attributes: (5) Access is denied
Solution:-
----------
- Go to the domain folder and delete the file ".security"
- Log in to your Plesk control panel --> Select the Domain --> Click "Check Permissions"
- On the next window, deselect "Check-only mode" --> OK
Now wait for the process to complete and try accessing the File Manager in Plesk.
