Usb connection malfunction I had samsung galaxy tab 10.1 gt-p7510 wifi only version. 
couple of weeks back, my tab couldn't connect to my pc or any other PC I've tried on.
It says the Usb connection malfunctioned and is not recognized.. 
whats the problem, how do I solve this...?
Some PCs may not recognize the Galaxy devices; if by PC you mean Windows, you can install the USB drivers by installing Samsung Kies.

One possibility is to try different USB ports, but since you have tried other PCs this seems less likely.

If the drivers are installed, the cable is the next likely culprit. Some cables are only for charging. You could borrow one to try, but data-transfer cables are cheap.

http://forums.androidcentral.com/samsung-galaxy-tab-2/302789-samsung-galaxy-tab-2-7-0-usb-device-not-recognized.html

http://forum.xda-developers.com/showthread.php?t=1861433