Can't install 2.2.1

[dil]

I got the notification that the update 2.2.1 was available. When I pressed install now, it rebooted and started installing the update. However, after few seconds it stopped installing and showed an exclamation point in a triangle. So, I had to pull out the battery to restart my phone. This has happened three times. My phone is rooted but I'm not running any custom ROM.
Any help on this?

 

[Droid DOES!!]

Do you have a custom recovery (CW or SP)?

DroidForums junkie!!

 

[dil]

I flashed clockworkmod recovery from ROM Manager