To test if an e-mail address is "legitimate" could mean a few things:
1. That the e-mail address *syntax* is correct - meaning that the address entered is valid per the RFC that sets guidelines for such things. This article looks useful for determining is an e-mail address is syntactically correct using PHP: http://www.linuxjournal.com/article/9585 2. That the e-mail address is actually real - meaning you could send an e-mail to it and it would be accepted. The only way to do this would be to create a program that connects to the mail server responsible for handling mail for the address provided, and seeing how it responds to the RCPT TO smtp command. If the server responds with a positive acknowledgement to RCPT TO (250), then it is telling you that it will accept mail for that recipient. Unfortunately, this is not always 100% accurate - some servers will accept mail for *any* address at their domain, and then bounce the message asynchronously. Microsoft Exchange servers are typically setup to handle mail this way by default, but can be configured to reject the recipient during the SMTP conversation. I imagine that someone has built an e-mail address validator that does this, but I couldn't find any by briefly searching on Google. HTH, -- Rob On Tue, May 25, 2010 at 7:25 PM, Luis Torres <[email protected]>wrote: > As Dan pinted out this is not possible anymore for remote hosts. > > Depending on permissions it might be an option for local accounts in a *nix > system but checking might only add complexity to your task so I'd steer away > from it. > > Good luck, > > LT > > > On Tue, May 25, 2010 at 5:31 PM, Dan Brown <[email protected]> wrote: > >> My understanding is that what you're looking for isn't available any more. >> You used to be able to send a command to a mail server and get a response >> back indicating if the address was valid or not. Spammers caught on to that, >> however, and abused it to farm addresses, so most email servers now ignore >> the command. You may have luck with some older mail servers, but it's >> definitely not 100% reliable. >> >> -db >> >> Dan Brown >> db interactive Inc. >> >> >> dmmontana wrote: >> >>> I have a client with an e-mail sign-up form on their site. In addition >>> to validating the syntax, they want to be able to determine on-the- >>> spot if the entered e-mail address is legitimate. I've come across a >>> couple of forms recently that do that but I can't remember where they >>> were. >>> >>> I did find the following PHP code: >>> http://code.google.com/p/php-smtp-email-validation/ >>> . However, I haven't been able to successfully implement it (I'm a >>> front end developer, not a programmer, and nothing I've tried has >>> worked). Has anyone had any success with this or another solution? >>> >>> Thanks! >>> >>> >> >> -- >> Our Web site: http://www.RefreshAustin.org/ >> >> You received this message because you are subscribed to the Google Groups >> "Refresh Austin" group. >> >> [ Posting ] >> To post to this group, send email to [email protected] >> Job-related postings should follow http://tr.im/refreshaustinjobspolicy >> We do not accept job posts from recruiters. >> >> [ Unsubscribe ] >> To unsubscribe from this group, send email to >> [email protected]<refresh-austin%[email protected]> >> >> [ More Info ] >> For more options, visit this group at >> http://groups.google.com/group/Refresh-Austin >> > > -- > Our Web site: http://www.RefreshAustin.org/ > > You received this message because you are subscribed to the Google Groups > "Refresh Austin" group. > > [ Posting ] > To post to this group, send email to [email protected] > Job-related postings should follow http://tr.im/refreshaustinjobspolicy > We do not accept job posts from recruiters. > > [ Unsubscribe ] > To unsubscribe from this group, send email to > [email protected]<refresh-austin%[email protected]> > > [ More Info ] > For more options, visit this group at > http://groups.google.com/group/Refresh-Austin > -- Our Web site: http://www.RefreshAustin.org/ You received this message because you are subscribed to the Google Groups "Refresh Austin" group. [ Posting ] To post to this group, send email to [email protected] Job-related postings should follow http://tr.im/refreshaustinjobspolicy We do not accept job posts from recruiters. [ Unsubscribe ] To unsubscribe from this group, send email to [email protected] [ More Info ] For more options, visit this group at http://groups.google.com/group/Refresh-Austin
