How do I uninstall 5.0 from my HTC One M7?

[AC Question]

About a week and a half ago I decided that I would finally upgrade to Android 5.0 on my trusty HTC One M7. I'd had a bad feeling about it for some reason, but I figured they'd had enough time to iron out the kinks.
Never again will I ignore my instincts. I had no idea any 'update' could be such a complete catastrophe. I could spend ten minutes listing the problems I'm having, but suffice it to say my phone is effectively inoperable - I don't even think I could make a 911 call without it getting dropped. It's that bad.
I know there's no official way to downgrade the OS, but I'm done waiting to see if the developers do anything about it. If I don't get 5.0 off soon I'm going to end up reviewing its flight capabilities.

The real problem is that I've tried looking up how to do this already, but I have no idea what the heck I'm reading in what little I've found specific to my model. I'm not a tech person; I don't get the jargon. I've never done anything to my phone beyond manually removing some of the included apps I didn't want, so if someone would be kind enough to just walk me through the process of putting some form of 4.4.4 back on my phone I would really appreciate it. Thanks.

 

[srkmagnus]

You need to use the RUU file to revert back to the previous versions. It's not easy, and the device could be bricked if you attempt it and something goes wrong. I would suggest taking a look at this blog post first and see if the suggestions in there help you: Android 5.0 Lollipop bugs got you down? Here's how you (might be able to) fix them | Android Central