My Documents folder changed to read only

Something changed. Under Documents/My Documents I have always been able to edit with no problems. But now My Documents folder has "Read Only" under properties. It is a shaded check box.
When I open a document I previously created I get a message box that asks - open read only, or open copy. Even if I open copy I cannot save it under My Documents. When I hit save it just highlights the file name and does nothing. Any help suggestions would be appreciated. Thank you.
I am the administrator/owner.

Maybe this will help you.

5down voteaccepted
The problem isn't that the folder is Read Only. Rather, because your folder was created on a different installation of Windows you no longer have NTFS security permissions to access (read) the folder.
Correct this by following these steps to take ownership and then grant yourself full access to the folder.

1. Right-click the folder > Properties
2. Security tab > Advanced
3. Click Change to the right of Owner
4. Enter Users into box and click OK
5. Enable the checkbox Replace owner on subcontainers and objects then click Apply
6. If prompted that You do not have permissions to read... click Yes
7. Completely close out of the Advanced Security Settings dialog
8. Right-click the folder > Properties
9. Security tab > Edit...
10. Add...
11. Enter Users into box and click OK
12. Enable the Full Control checkbox then click OK