Have old PCs sitting around? Why and how to upgrade them to Windows 10 now

As the deadline ending Microsoft's free giveaway of Windows 10 upgrades looms closer, it's important to take stock of your hardware. Do you have forgotten hardware that should be upgraded?

Old computers

How many leftover PCs do you have sitting around in closets, on shelves, and in the form of virtual machines? In my case, I found three mini PCs, a couple of laptops, a netbook, and four towers that are sitting on shelves in the garage.

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Here's the next question: how many of them have you upgraded to Windows 10? Yeah, I know. If you're like me, you haven't upgraded any of them and you're not even sure what version of Windows those old machines are running.

I know I have a pile of XP machines, one Vista machine, and a whole bunch of either Windows 7 or Windows 8 machines, not counting all my VMs (which are mostly Windows 7).

While I'm not now using those machines, there's always the chance I'll want to put one back in service. For example, some low-end 3D printers and CNC machines require a PC to drive them. Rather than dedicating an active laptop, I'm much more likely to dig into my storehouse of old machines and press one of them into service.

I definitely don't want to be running XP on anything. I've found moving to Windows 10 to be generally harmless and actually makes older machines perform better. Plus, given that the free Windows 10 upgrades are expiring in July, it makes sense to move these machines to Windows 10 now.

There are some issues. First, there's no guarantee these old boxes will be compatible with Windows 10. It's a good idea to run the Windows 10 compatibility checker to find out if Windows 10 will work.

That brings me to one other issue. There is no free upgrade path to Windows 10 from XP or Vista. To upgrade to Windows 10 from a machine running XP or Vista, you either have to buy an actual copy of Windows 10 (in which case, you might as well just keep the old boxes sitting in their bins in the garage) or first upgrade to Windows 7 or Windows 8.

That, too, might be complicated. It's particularly difficult to get a Windows 7 install disk from Microsoft. The good(ish) news is you can buy copies of Windows 7 from Amazon and eBay ranging from about $50 to about $80, which is still cheaper than buying Windows 10 directly from Microsoft -- although, admittedly, a lot more work.

I have a ton of old licenses, so I'm not going that route. I'll simply upgrade each machine to Windows 7 or Windows 8 (for those that need upgrading) and then run the Windows 10 upgrader.

Finally, I would advise you not to connect your XP machines to your network. While you're probably safe, I have seen how polluted with malware Windows XP can get, so I'm actually going to both keep my remaining XP machines off the network until I've upgraded to at least Windows 7.

I'm even going to power down my router in case any of the machines tries to tap into the network via WiFi. It's a small price to pay to make sure the network stays safe.

What about you? How many old machines do you have sitting around that should be upgraded to Windows 10?

By the way, I'm doing more updates on Twitter and Facebook than ever before. Be sure to follow me on Twitter at @DavidGewirtz and on Facebook at Facebook.com/DavidGewirtz.