IPad 2 cannot sync with Windows 7 machine but can sync with Mac Book Pro

Question

I connected the iPad to my Windows 7 machine straight out of the box and tried to register it for the first time. It showed up in the device list for the first 3 minutes and then disappeared altogether. Thinking this is just some small error, I started troubleshooting using this guide http://www.apple.com/support/ipad/assistant/itunes/
http://support.apple.com/kb/HT2292
after doing that 4-5 times, I still had not found a solution to the problem. I made sure that my computer had the Apple Mobile Device Drivers installed in it. After all my iPod can easily connect to iTunes, but not the iPad. There isn't a problem with the usb cable because I used the same cable on the iPod and it worked like a charm. The iPad gets recognized in the Device Manager as an Apple Product, but does not show up in iTunes at all. This problem has frustrated me quite alot. I also tried to use my friend's Windows 7 machine, but to no avail. It did not connect to his computer either. Finally as a last resort, I tried to connect it to a another friend's Mac Book Pro [iOS Snow Leopard], and like clockwork, it connected and showed up in his iTunes. This is what surprised and outraged me the most. After spending 5-6 hrs troubleshooting the connections on my Windows 7 machine, uninstalling and reinstalling applications, drivers and finally the OS itself, this iPad connects seemlessly to a Mac Book within 1 minute. I could synchronize data, songs and the like on the Mac Book, but I can't even get this iPad to show itself on a Windows 7 machine. I am truly at my wit's end with this problem. Could anyone please help me with it? I would surely be grateful.

Answer 1

Here is my statdard reply, most of which you have already done. You may wish to try the others!
Firstly, make sure that your device is not hidden (left hand pane). If it just reads device then toggle between SHOW and HIDE.
Secondly, try all the other ports on your computer, even a number of times.
Thirdly, if you have another computer try plugging your device into it without taking any action, give it a moment, remove it and try it back in your other computer again.
Failing all that, see here - http://support.apple.com/kb/TS1538 for Windows and http://support.apple.com/kb/TS1591 for Macs
And failing all that put the device into Recovery mode. See here and note the paragraph 'If you restore from a different computer.... ' down near the bottom of the page -
http://www.apple.com/support/ipad/assistant/itunes/
https://discussions.apple.com/message/17579027#17579027tr