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It's hard to say why that's happening, and there's not a straightforward recommendation.

When you get down to the heart of the thing, it's simply just long, long past time to move off of XP.   We're not even allowed to have a WinXP machine in our building at this point, much less have it connected to the network.  As you can imagine, we're not investing a whole lot into XP at this point.  It's well beyond it's supported life, adoption is down in the single digits now, and it's just going to continue to present ever-increasing friction for you.

Comparatively, a really nice Win10 machine will run you $400.  If you just need a browser, a really decent Chromebook will set you back $250, and if you want Apple hardware, but are cost-sensitive, Walmart stocks refurbished Mac hardware on their website at really reasonable prices.