Only a partial stack trace was posted, so it's not possible to look back to where exactly this is originating from.

However, I am fairly sure it is a case of the content_reviews addon being removed, then somehow some of the files for it coming back or still being there.

As it was on a Windows server and I recall a user mentioning they didn't know how to configure their Windows server with file permissions (FTP, but actually write permissions for the install directory would have worked), it could well be the addon only uninstalled from the database but the files are left behind.
It's important to work out how to configure IIS to have full recursive write permissions and/or a working FTP server, but that's outside the scope of any Composr bug/support, as it's relating to the server configuration itself.

Sorry for the bug. It wasn't related to filesystem permissions, it was however related to the content_reviews addon.

I have done a fix to sources/resource_fs_base_class.php here:
https://raw.githubusercontent.com/ocproducts/composr/97bd3abe3c227ccd932cbd58e1365341ea4c5309/sources/resource_fs_base_class.php

Thank You that fixed it.

Jim