I have purchased a Canon MX726. It installed beautifully both with USB and WiFi. However after a short time I could not contact the printer with wifi, with my windows 8.1 but my wife can use it with wifi on windows 7. I have contacted Canon and on two occasions they stepped me through a solution but last time their solution solved nothing. I believe that an update is responsible for taking out the driver,  there is no information for windows 8,1 in the Canon manual, I do not get updates from canon so I conclude that it is windows updates that is causing the problem. Incidentally the last lot of updates caused both my computer and Maureens to drop Chrome.  What is happening?

Hi,

Is there any error message when you trying to connect the printer through WIFI? Can this connection be established? 

If you concerned it is Windows Update problem, you can open Windows installed update to check if there is any update was installed recently. If that it is, try to uninstall these update for test.