Rules of validating email addresses

While DNS validation / SMTP validation seem like no-brainers, I foresee problems where the DNS server/SMTP server is temporarily down and a user is unable to register somewhere, or the user's SMTP server doesn't support the required features.

How might some experienced developers out here handle this?

I just tried that validation rule (which appears to have come from here) and it worked for the most common cases.

It's not bullet-proof, but I'm sure that it is sufficient for lots of applications.

Hey i am did this validation rule for a project i did 3 months ago, i readead your thread and found the way i did it. *") And (Not Like "*[ ,;]*")) it works perfectly and the company i just built a database for have no issues with it, it can even tell if someone enters " accedentally due to them not configuring their language settings properly. cheers Remi Hey i am did this validation rule for a project i did 3 months ago, i readead your thread and found the way i did it. *") And (Not Like "*[ ,;]*")) it works perfectly and the company i just built a database for have no issues with it, it can even tell if someone enters " accedentally due to them not configuring their language settings properly. Copyright © 2008 The Extensible Markup Language (XML) is a subset of SGML that is completely described in this document.Its goal is to enable generic SGML to be served, received, and processed on the Web in the way that is now possible with HTML.An email address identifies an email box to which email messages are delivered.A wide variety of formats were used in early email systems, but only a single format is used today, following the standards developed for Internet mail systems since the 1980s.

Rules of validating email addresses