Hi ejalcan,
So that we can help with your issue, we're going to need a little more information about your situation. Could you answer a few questions?
(1) How are you connecting your MF227dw to your Windows 7 computer, with a USB cable or via your network?
(1-1) If it is with a USB cable, is the USB cable connected directly from the back of your printer to your computer? Or is the printer connected to a USB hub or some other external USB device?
(2) So we know the scanner is working, are you able to make a copy after placing a document in your MF227dw then pressing the COPY and START buttons?
(3) Are there any other programs open on your computer when you attempt to scan with the MF Toolbox?
If you need immediate assistance and you're in the USA, please click http://Canon.us/ContactCF for our US-based support. If you're outside of the US, please click http://Canon.us/4xf7 for support options.
Did this answer your question? Please click the Accept as Solution button so that others may find the answer as well.