now, if you're still reading then that means you have 4.3.3 shsh in cydia so now we'll attempt to use TU to pull that shsh from Cydia so you can save it in your pc.

now, what version of Tiny Umbrella you're using? you should be using the latest one. download here:

http://thefirmwareumbrella.blogspot.com/

then is your ipad switched on and in usable condition? have you synced before and itunes can detect your ipad? if yes then when it's plugged in an itunes detected your ipad, open TU and close off itunes. TU should be able to list your ipad on the left side column. dont forget that TU should be located in you desktop and not run from pendrive.

if cannot, restart your PC and turn off all firewall & antivirus, try again
if still cannot, try plug into another USB port and repeat
if still cannot, try with another pc/laptop that has TU and repeat
if still cannot borrow someone else's cable and repeat the above.
last effort if still unsuccessful, borrow someone's Mac/Macbook and try the above again. (i read that plenty of cases like this, cant do anything in windows PC, but successful in Macbook/iMac)

if still cannot then i dunno what else to suggest. good luck