[Asus  Eee Pad Transformer Prime] Lostsorrow:
Thanks so MUCH this solved it for Winblows 7 64 bit. For others having the same problem on Winblows 7 64 bit (should be the same for 32 bit miuns the X86 Directory)

1. Go into settings on the prime and make sure USB debugging has a check in it in under SYSTEM > Developer options > USB Debugging

2. Plug your prime into your Winblows 7 laptop and let it install its drivers. Open up device manager by going to Start > Control Panel > Hardware and Sound > and click on device manager under devices and printers. If you see at the top of device manager ASUS Android devices and when you expand it you see ASUS Android Composite ADB Interface you already have the ADB drivers installed and can skip down to #6

3. Go to ASUS website and download the USB drivers for the TF201. Download Vipermod Primetime 4.6 here for the ADB drivers http://goo.im/devs/viperboy/Prime/viperMOD_PrimeTime_v4.6.zip then extract the zip file to a normal file. You only need the drivers from the tool.

4. Plug your prime into your Winblows 7 laptop and let it install its drivers. Open up device manager by going to Start > Control Panel > Hardware and Sound > and click on device manager under devices and printers.

5. You should see the prime listed under portable devices. Uninstall the driver then update the driver manually. Browse to the folder you created from the Vipermod primetime zip. Make sure there is a check in check sub folders. Winblows should detect the drivers and then convert the prime to a ASUS Android Device.

6. Go into settings on the prime and make sure there is no check in Launch ASUS Sync under PERSONAL > Accounts & Sync > Launch ASUS Sync

7. Press Control, Shift, Escape at the same time and make sure there are no instances of ASUS Sync or Splashtop runnung in services in Winblows 7.

8. Download and Install the latest Android SDK. I installed all the libraries and such just to be on the safe side. http://developer.android.com/sdk/index.html

9. DISCONNECT YOUR PRIME FROM THE USB AND REBOOT YOUR PRIME AND YOUR WINBLOWS LAPTOP. After both devices reboot plug in your tablet into your Winblows laptop.

10. Navigate to C:\Program Files (x86)\Android\android-sdk\platform-tools and click on the ADB file. A command prompt will open and spool up a bunch of stuff then close. All the stuff spooling I am assuming was the ADB server starting.

11. Hold down shift then right click inside platform-tools folder and select open command prompt here. You should be in a command prompt window showing the directory C:\Program Files (x86)\Android\android-sdk\platform-tools

12. type adb devices. You should see your primes serial number pop up.

13. make a test file in the platform-tools directory, i just used a simple text file to test then type:

adb push test.txt /sdcard/

It would be easier to just put the Rom you are going to flash in this directory so when it is time to push the rom it would be:

adb push nameofrom.zip /sdcard/

If SDCARD not recognized try:

adb push nameofrom.zip /system/media/

14. browse to your sdcard and you should see your file there. If you are already in the sdcard folder window on your prime, leave the folder then come back and it should be there.

15. You should be able to push files now after superwiping. You may need to push to /system/media/ if /sdcard/ is not found. Make sure you have all the / in the directory structure when pushing.

16. From inside recovery select install zip from sdcard and browse to the folder you pushed it to then flash away.

If anything seems incorrect or out of order please let me know so I can correct it. If this helps you congrats but if not I'm sorry. This is how I got it to work.