While it shouldn't matter, I've noticed that occasionally hotmail and yahoo (more often with hotmail than yahoo) receive the e-mail then delete it straight off, even though they aren't supposed to.
If you have tried one of those types of e-mail addresses and have another one you can try, I suggest you try that.
The reason it goes for 24 hours then stops, is because most registrations require the confirmation code within 24 hours, and if it's not received, then the registration is cancelled.
