Why is "Verify Backups" in the Time Machine icon menu disabled? I learned in Upgraded to Lion: Time Machine spends a LOT of time indexing backup that if I hold down the option key and click the Time Machine icon in the menu bar, the "Back Up Now" menu item changes to "Verify Backups".  But for some reason, on my MacBook Air, "Verify Backups" is disabled (greyed-out).  How do I find out why?

I'm running OS X 10.7.1, and have FileVault turned on for "Macintosh HD" (my internal storage).  My Time Machine backup is to an external USB HD, which I've encrypted.


Could that be why?  Does Lion not support "Verify Backups" with an encrypted Time Machine HD?
&quot;Verify Backups&quot; is applicable only to backups on network drives.  It will be greyed out if you are backing up to a local drive.
Apple should have been clearer in indicating this.
From Finder &gt; Help &gt; Verify your backup disk

Verify your backup disk
If you back up to a network disk, Time Machine periodically verifies that your backups are in good condition. If you like, you can perform a verification at any time.

Open the Time Machine menu in the menu bar, press the Option key on your keyboard, and then choose Verify Backups.