This is great - the EOS Utility was refusing to enable the 'shoot' button - after this it worked like a charm, thank you! "Go ahead and plug in the camera and turn it on. Open Device Manager. Under the View Menu, check "Show Hidden Devices". Scroll down to the bottom of the list, expanding categories as needed, and find "Canon Digital Camera". There may be more than one copy present. Double click on each "Canon Digital Camera" in the list, click on the Driver tab, click Uninstall, and CHECK THE BOX that says "Delete the driver software for this device." Then click OK. Do this for each entry labeled "Canon Digital Camera." Then, with your camera still plugged in and turned on, click the Action menu and choose "Scan for hardware changes". "