- my mouse and keyboard take up to 5 minutes to start working after getting to the log in screen. They are both brand new, 2016 input devices - Corsair Strafe RGB and Logitech G300s.
- my computer wakes up randomly around 1am, every single night. I've tried troubleshooting the issue for months, and there doesn't seem to be a cure. I've disabled the ability of devices to wake up the computer, I've disabled the wake up packets, I've disabled wake up timers, I've even disabled windows updates completely. In the final act of desperation, I went back to Windows 7 - no issues. As soon as I upgraded to Windows 10, computer wakes up every night. powercfg -lastwake just shows that the computer has woken up because of "unknown source".
- Dragging windows between different monitors is a joke - if you hold your cursor in one corner of the window, when you move it to another monitor, it's a lottery where it will be. Maybe the cursor will be on bottom right corner, maybe it will be in the middle, maybe it will be off the window entirely, who knows.
- I had an "Epson Scan" application to use my scanner. Except that one day I switched on my computer, and it was gone. I found out that windows deleted it completely, because it "wasn't compatible with Windows 10". Except that it never told me that it did that, and the application works perfectly fine. I was in a hurry as well, and I spent 30 minutes scratching my head wondering where the app went.
- Network stops working from time to time - just shows me "there's an error with the network device" and only a reboot fixes it. That's with an Intel I217-V network card which is supported by Windows 10.
- The start menu is a mess - I've had several things pinned to it, then after an update they went all over the place, and had ads interleaved with them. Ended up paying for Start10 in the end.
- Speaking of Start Menu - in Windows 7, you could click on start, then start searching instantly, and also get results pretty much instantly. Windows 10 - you click start, then wait for stupid cortana to load which takes several seconds, then you search, and then you have to wait again. Much slower than windows 7.
- Photo viewer stopped working completely one day. I use it to browse photo files every day, and then one day I got an "internal system error" when trying to open it. After searching the web for the message I gave up on trying to fix it - it still doesn't work to this day, I had to switch back to the old Windows 7 photo viewer.
- Usability is attrocious. The "show" desktop button is literally 2 pixels wide, and there's no way to make it wider. Dragging windows near the top of the screen automatically pins them to that monitor, so you can't move the window to a different monitor anymore - you have to let go, and try again. You also need to do it quickly enough to make sure it doesn't snap to the edge of the screen or you will have to do the whole process again since you lose the ability to move to different monitor at that point. You could disable this behaviour in Windows 8.1, but you can't in 10.
- Minor nitpicks: File explorer decides randomly I think, which devices to show on the left - it has my drive C and E, despite the fact that I use my drive D all the time, and almost never open E. Removable devices sometimes appear on the left, sometimes they don't, it's a lottery. In network manager, when you move the cursor next to a network device, first it gets a faint blue outline, then a dark blue outline, but they don't overlap. What are they for? The first one doesn't do anything, it's not even a selection outline. It just looks amateurish and doesn't add anything.
- You can disable tracking, and it will just come back after an update or two. I'm 100% sure that one is actually illegal.
- Webcam is not detected in Windows 10, unless I unplug it and plug it back in, works perfectly fine on the same machine on Windows 7. That's probably a driver problem, but I frankly don't care.