I have Windows 7 Home Premium N on my PC. I installed EOS Utility for mt 1100d and found the PC would not recognise the camers.
Aftrer long talks with Canon and Microsoft a Canon Tecci found the solution.
Go to http://support.microsoft.com/kb/968211
Halfway down the page is a download for Windows Media center that contains the missing drivers.
Click on download and then click on the right windows operating system,its either the64 or 84 bit.
Download it and all will then work for you.
if you download the wrong one dont worry just download the other one all will be ok.