I just now tried KnightOS because it said I could always install TI-OS back. I have been trying hard to figure it out, but I have no idea. When I try to "Receive OS Upgrade", It errors halfway through. It doesn't start to transfer, only attempts to. I have a Linux with TiLP2 installed, but it won't connect to the calculator running KnightOS. It is a Ti83+. If I need to give any more info, I can. Please help though.

Remove one of the AAA batteries. Press and hold the [DEL] key. While still holding the [DEL] key, replace the battery. While still holding the [DEL] key, press ON if the calculator is not already on. Hope this helps!

I've tried, but it just won't connect.

It says: "Waiting... Please install calculator software now."

As soon as TiLP check if it is a TI-92, it says: "ERROR! Press any key to turn off the unit. Then turn unit back on."

So the transfer won't even start.

Use TI Connect to reinstall the OS, not TiLP

I'll have to try that tomorrow then because I only have access to Linux. I just hope that works. It should though. Thanks Mateo.

Unfortunately, TI-Connect doesn't work on Linux, so TILP would be your only option there. Do you know anyone else with the same model of calculator from whom you can transfer the OS?

I have a windows computer. I just don't have it right now.

Oooh, gotcha, I misread your post. I hope that TI-Connect does the trick for your calculator.

Thank you. I never though of trying TI-Connect. I was a little panicked because of my Algebra and I had a quiz tomorrow. It worked though. Thank you