Hi all........ frustrating this problem isn't it?
The following may help you - it solved the problem for me. (MacPro - 10.6.2)
Did all of the above, downloaded the various updates, patches, you name it..... Nothing! - just the scanner aspect announcing under Bonjour, but no printer.
So.........
1) reset the printer back to 'factory' from its settings menu.
2) DELETE all instances of Canon installed software for this machine (and any earlier models if you had them) - Use Spotlight to find them if necessary .... but also remove the Canon folder in the main Library > Application Support.
3) Empty the Trash (restart if a few are 'in use' and then delete - they should go)
4) Get your printer recognising your wireless network using the 'easy' option in the settings > wireless menu such that the printer at least reports 'connected OK.
5) Re-install software from CD - run thru' entire process as before and see if the Canon network utility can 'see' the printer and do a speed test on it..... (don't worry if you got this far before - it just establishes whether the printer is technically 'there' wirelessly regardless of whether the Print Box can see it).
6) Download updated CUPS driver from Canon Site at:
http://software.canon-europe.com/products/0010757.asp
Get the file: mp640sosxcp102620ea8-2.dmg and install it.
7) From the Printer's own panel, check its IP address from Settings > Lan settings etc....... probably reads something like 192.168.1.4 or similar.
8) Open your web Browser and type that address into the URL bar (no www etc, JUST the number) and hit ENTER....
With luck you should be able to see the printer setup menu via CUPS (slightly 'odd' looking interface with 'Canon' in the top left corner) - Click ADVANCED.
9) The TOP page gives you an overview of the settings
NETWORK settings - Make sure the network / security details look correct.....
Network address IPV4 - I changed my printer to a fixed (static) IP address outside of the lower range e.g. mine went to :- 192.168.1.51 so as NOT to be dynamically changing and 'out of the way' of other guest machines attaching to the router at lower numbers.
CLICK OK.......... noting that you've changed the address so the browser will lose contact with the printer as soon as you click the OK button.
Type the new network address into the URL bar, hit ENTER and re-connect to printer.
Click Advanced .....
10) OTHER SETTINGS:-
I changed the following:
LLTD setting - enable
Bonjour setting - enable
Service Name - CHANGED from long string to shorter, obvious name - MP640_Wireless
LPR Service - ON (not sure if this is relevant)
LPR Protocol - Enable
Click OK to save settings to printer.
Exit Browser.
NOW - the important bit...... from System Prefs > printers > add ➕ a printer
the new name showed up ( MP640_Wireless Bonjour).
Select it and click ADD.......... for some reason this doesn't add it to the Mac's printer list BUT DOES generate another wireless service in the list called:-( MP640_Wireless canonijnetwork)
Select this new service and click ADD and BINGO!! - the MP640 (printer) appears in the usual printer list and WORKS!
A bit long-winded and not entirely sure what's going on here except something in the driver setup is being 'woken up'.
We shouldn't have to do this but I hope the above helps someone out.
Regards to all
Spiro'