DF_MailStuff 4.0.411.15
F_MailStuff is a freeware .NET component useful in any circumstances you need to validate/check email address input by the user.
DF_MailStuff is also much more:
isEmailValid: use this method for validating email address checking syntax (even bad words) and/or validating domain (syntax check, dns lookup, top domain check, MX check, anonymous domain check, email existing against remote smtp server)
catchEmails: use this method for retrieving all email addresses contained into a text
DF_MailStuff returns detailed error codes
No external references but .Net 2.0 framework: just download ad use it