I just bought the T2i and used a friend's external flash on the camera. Prior to using the external flash, everything worked great. The external flash is currently NOT on the camera but the camera thinks it is still there. I've reset the settings and custom settings from the camera. I've left the battery out for 10 minutes and tried again but nothing, it still thinks the flash is there.
If I put the external flash back on the camera, it works and fires the flash but as soon as I take it off, it won't launch the internal flash. If I go to Flash control and then Built-in flash func. settings it says "This menu cannot be displayed. External flash is attached."
Can anyone help???
I've answered my own question... after some digging I stumbled upon a flickr page. There's a micro switch under a metal flag on the inside right side of the hot shoe. If it's in or in too much when the external flash isn't present, the camera will think it has an external flash!. I lifted the flag up a tiny bit with a set of tweezers and low and behold, i have a working flash. I've tried the external again and taken it off and I'm still good to go!
Here's the post!