I have a Canon XSi DSLR. For some reason, in any of the creative modes, all the buttons lock up and I cannot take any pictures. If the set the focus to Manual Focus, then I am able to take pictures but still the menu button etc are disabled. Everything works fine in Auto Mode and all the other preset modes like Portrait, Landscape, Night, Sports etc. I have tried it with different lenses and it is the same behavior.
Also, when I remove the lens, everything seems to be fine (i.e. menu button shows the menus , shutter works, flash works).
What could be the problem? I have tried resetting the camera and all the C-Fn functions....