Flash not popping up, Err 05 in 20D

With Camera in P, I can't get the flash to manually pop up with the pop up button. It appears to try three times and then gives me an Err 05. Other threads have mentioned a micro switch under a rail in the hot shoe. But Err 05 doesn't seem to accompany that. Any thoughts?

Thanks

Stew

Check the switch - they may not say ERR05, but that's essentially what they get.

That happens on my 20D sometimes. My crude diagnosis is that something is buggy in the mechanism that releases flash. Try wiggling the flash as you press the button. It generally works for me.