There are not “a lot of variations of email validating”.There are only two: the right way, and the wrong way.

Using regex for email validation is extremely hard to do right and there are literally hundreds of examples on the net of validators that get close... But that's only a small part of the problem anyway.

Your absolute best bet is to drop trying to validate the address and simply send the messages while telling the user which addresses failed.

I want to have a textbox where I can type all email addresses which I want to send a message...

However I want to add a validator there so the user always has the correct syntax and therefor, use that string on c# and send the message properly.

but this will have to do) now I want to addapt this regular expression to an validator: email ( (,|;) [SPACE]* email )* example of results i want: [email protected], [email protected],[email protected]; [email protected] hope you can help me with that...

Thanks in advance What you have won't work to validate email addresses.

I cannot guarantee that perl incompatible pattern engines will correctly handle the recursion. I would steer clear of the ones that try to be clever and have a list of all the tlds because they are being added to quite regularly (such as the domains recently).

Including the list in your regex will just cause you headaches down the line.

I tried this one on your string: which I just grabbed off of and removed the ^ and $ at the start and end.

If you run that through Regex class you should get a Match Collection back but im not sure if you are working in .net?

May be okay for your purposes, but just pointing it out.