registeration for gre retest

<p>I had taken my gre on september 29, 2008. It seems I get to retake the verbal section for free because there was something wrong with computer algorithm at that time. I do plan to take the verbal section as my verbal score is very low. its 390 ; a score that I had'nt quite expected. But the problem is I dont know how to register for the exam. All that ets has sent me is a voucher number..I chekd out the gre website but no details have been given..cud u guys help me with this?</p>