Every time Fences has an update available its notification kicks me out of whatever I was doing. Today it cost me an online match, which as you can understand is infuriating. How do I disable the update notifications? Frankly unless there's some kind of major security bug I don't see any reason to ever update it. I've been through the Configure Fences menu but the option doesn't seem to be on any of the pages.
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This happened on past updates too. Basically it'll keep happening until you actually click the "yes reboot now" button. My guess is that something is loaded into memory that gets run at startup when you click yes, but clicking no or rebooting in any other way does not start whatever process is being started.
Or you can assist people that come to the forums so that everyone can benefit from the answer. This isn't a one off issue nor is it the first time it happens, so there's a lot of people that are going to come here looking for a solution.