[SoftTalker]

Mailinator addresses, and other "disposable" email service addresses, are often rejected by sites that ask for an email address to create an account.

There's sort of a race condition between how quickly new "anonymous" email services appear and how quickly they are banned by other sites.

[Komodai]

Then just use temp-mail.org, they rotate domains very frequently, they have been around for some time now as well.