It would seem that the dreaded "Error 01: Communication between the lens and body has failed" errors on my canon EOS 1100D camera when using my EFS 18-55 lens, is not such a unique problem, nor is the frustration. Seems a lot of other have found changing lenses and removing batteries give temporary respite on a variety of other canon models and lenses, with different error numbers but similar cause, or should I say lack of obvious cause. My manual suggest cleaning the contact, with a soft lint free cloth, but I have found this never seems to fix anything.
The various photography forums are full of request for advice and most have the same recommendations, remove lens, remove the memory card and remove battery, wait a while and then restored the items in the reserve order. This occasionally works for me and never when I really need it to get a decent image. My investigation seem indicate I need to remove the lens switch to manual and set the f-stop lower than f4, and then remount the lens and I just might get a shot of two more.
If all else fails … you can always read the notes on the canon USA site offering some explanation and understanding! For the very important advice don't use an eraser to clean the contacts! Ok cannon might have a communication issue with their cameras owners as well. So that just leaves joining the queue of frustrated camera owners and use a different lens.