The computer does not recognize the sidekick

check the pins

i think its your SD reader becuase i have had da same problem

Do you hear any beeping or noises from your PC when plugging in the device to your USB? Is it even recognizing something is being plugged in/ If so it should prompt you to download proper software. Have you installed your software on the computer that came with the phone? Sometimes it needs to be there but should still at minimum see a new device when pluggin it in. If no response when plugging in try replacing the cable or try on different USB/and or PC

For the sidekick 3 to be seen on your computer, you need to have a memory card installed. The Sidekick 3 internal memory is not accessible at all

Here is your solution: 
Now follow these steps to a "T" don't do any shortcuts etc, this is "across the board" for all sidekicks it worked on my Sidekick Slide and on my Sidekick 2008.

1. Remove battery and the SIM card from the devise.
2. Flip the sidekick open; press and hold the letter "r" on the keypad
3. While holding the letter "r", place the battery back in the device. DO NOT INSERT SIM CARD YET.
4. The Sidekick will restart itself twice. Please make sure not to let the letter "r" go until it has fully rebooted.
5. Once it has fully rebooted, remove the battery, reinstall the SIM card and battery.
6. Power up device.
7. Once the device has fully rebooted, all prior information should be erased from the device and it should be restored back to the default factory setting.

Phone"--->click menu (the three lines)--->highlight and click "settings"--->highlight and click "system info"--->scroll down to "radio firmware" if it says unknown

this has been a plague with sidekick phones

All you need is to add the Data plan on, and you should be set to go and be able to create your username and password.

If their username is still showing up on the phone, call customer care and tell them your situation, and they'd be happy to help you clear the information off.

well finding stores is a bit difficult and im not aware of where you live. BUt if you live in Brooklyn, NY, then downtown brooklyn on futon mall street, theres a stores which sells sidekick screens. Chances of finding an ID screen are unknown to me. By the way this store is close by Futon Mall street and Jay STreet

If you're getting, 'radio firmware unknown'
Then the radio module is dead.
The radio module wont respond to give the firmware version.

You need to contact customer support at T-Mobile and get the device proffesiony repaired.