Ellen Myrup, give this a try and see if it helps.
[http://tricks-collections.com/reset-printer-canon-mp140-mp160-mp180-mp210-mp220-mp460-mp470-mp500-mp510-mp530-mp600-mp610-mp800-mp820-mp810-mp830-mp960-mp970/|for] more instructions
Disconnect the power cable
Hold down power button
Reconnect the power cable
With the power button still down, press twice the “Cancel/Stop” red button
Release the power button
The printer is now in factory mode…(wait about 30 seconds until it says “idle”)
Press the down arrow (next to the “OK” button) until it says “Shipping Mode 1”
Press the “OK” Button
Now with it displaying “Without Cleaning” press the power button
A test page should print
Now open cover
Disconnect the power again
Take both cartridges out like normal
Close cover
Reconnect power cable
Press power button
Replace cartridges
The other way to reset it would be by using MPtools and the instructions are [http://tricks-collections.com/reset-canon-pixma-mp150-mp160-mp170-mp180-mp450-mp460-mptool-software/|here] MPtools should have come with your printer. Good Luck and let us know if it worked.