My trusty Canon 350d was sick, it would switch on but not take a shot.  I tried removing the battery for a while to see if it would reset but it didn’t make any difference.

I came across a post on dpreview.com which said to try the following:

1.) Turn off the camera.
2.) Remove both camera batteries (The main battery and the internal date/time battery which is beside the main battery)
3.) Close battery cover.
4.) Turn on/off switch to “On”.
5.) Let camera sit for at least 15 seconds.
6.) Turn on/off switch to “Off”.
7.) Re-install both batteries and turn camera on.

And it worked! Back in business…