System hardware specs and Windows OS information?
If you have full admin rights to the folders then you can go in and change the folder/ file permissions.
Are you aware of any updates, new software, etc. that caused the change to Read Only (RO)?
There may be something else going on so be sure to backup all important data before doing anything. Verify that the data is recoverable and readable.
That way you will still have the data even if only RO.