Vista driver is here
Canon U.S.A. : Support & Drivers : PIXMA MP140
have you tried this driver ?
you may want to completely remove the old drivers
remove printer drivers
Open Printers and Faxes.
On the File menu, click Server Properties, and then click the Drivers tab.
In the Installed printer drivers list, click the driver you want to remove, click Remove, and then click Yes to confirm.
Note
To open Printers and Faxes, click Start, and then click Printers and Faxes.
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This tutorial will explain how to delete Printer drivers from windows 7/Vista
1. Delete the printer from control panel -> printers
2. Open Services.msc and stop and start the Print Spooler service
3. Open Print Management(Open command prompt, type in printmanagement.msc or type print management in to the start menu search box)
4. In Custom Filters -> All Drivers right click the printer driver you want to remove and select Remove Driver Package
5. Install new printer driver.
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