If the folder is one that you customized using the Customize This Folder Wizard in Windows Explorer or a standard Windows customized folder (e.g., the Fonts folder), you might not be able to remove the read-only attribute or you might receive an error when you try to write a file to the folder. In either scenario, Windows is preventing you from writing to the folder because the OS is using the read-only flag to determine whether the folder is a system folder.

To work around this problem so that you can modify a folder's read-only status, you can tell Windows to use the system flag instead of the read-only flag to identify customized folders. To configure Windows to use the system flag, perform the following steps:
1. Start a registry editor (e.g., regedit.exe).
2. Navigate to the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer subkey.
3. Select New, DWORD Value from the Edit menu.
4. Enter a name of
UseSystemForSystemFolders
and press Enter.
5. Double-click the new value, set it to 1, and click OK.
6. Close the registry editor.
7. Reboot the machine for the changes to take effect.