Backup damaged by last upgrade

[Mike Adams]

After installing the last Time Machine and Airport update my backup disk has become read-only. Attempts to change permissions fail since the Sharing and permission are grayed out

 

[aicul]

Have you resolved this issue? I have the same problem, although not in relation to an OSX update.

 

[Mike Adams]

Only by erasing the disk and starting a new Back-up. No problems since then though