I just realized I have a $100 voucher from my ISP, I already have a Adcenter account 3 days old, can I still use it?
you may still be able to apply it on your billing tab - but it may just be safer to create a new account unless you've already set up lots of campaigns.
It's just like adwords, you have to use your vouchers when you're registering, well that's as far as I know, I may be wrong, I havent used these programs yet.