first, due to the way the first sentence is worded, I am worried you tried with the keypad not connected to the calc , if that's the case, it needs to be plugged in the calc but unfortunately, TI-Connect appears to be random with the TI-Nspire. On my Windows XP SP2 computer, to use my TI-Nspire 84+ mode, I have to use the old black serial link cable from 2002 that is plugged in the I/O port, otherwise with USB, TI-Connect won't find my calc. On Windows 7 64 Bit with the TI Connect 64 bit patch, it works fine with USB.

In some cases, TI-Connect on my XP comp will fail to recognize my TI-83 Plus too, then another day it will work fine. Idk why this happens. The best way on non 64 bit OSes is to use TiLP I think (found on ticalc.org)

When installing TiLP I think i just chosen the default settings. But it has been almost 3 years since I installed it on my old computer (this comp only has TI-Connect 1.6.1) so I doN't remember anymore, and I don't feel like messing with TiLP + 64 bit issues atm by trying installing it myself on this new comp, so I can't help much atm, sorry, hopefully someone else could help, though. Bump your topic if no one awnser tomorrow