So I had an old ~1.7ish Nspire Clickpad that I lost the keypad for. I'm taking the ACT this sat, so I ordered a touchpad-keypad off of amazon. Upon booting that keypad, I got the "unrecognized keypad" error, but I didn't have the original clickpad to update the OS with. Instead, I booted into the recovery menu and formatted the OS. Upon rebooting, I was brought to the "Install OS now" screen. Success!, or so I thought. I can't get it to show up in Computer Link on either of my PCs.

Help!

Welcome on the forums. I'm unsure what causes the calc to not be detected. In any case make sure you restarted, but otherwise you may have to try TiLP (uninstall the computer link software and its drivers first). Else you might have to contact TI-Cares. It might not be the calc, unless there's something defective with the USB port.