As of Aspose.Network 220.127.116.11 the MailAddress object does not accept certain valid email address formats. For example: firstname lastname"@domain.com would throw an exception as an invalid format "The specified string is not in the form required for an e-mail address."
To be fair, it doesn't work with System.Net.Mail.MailAddress either, however according to ftp://ftp.rfc-editor.org/in-notes/rfc3696.txt that along with a lot of other bizarre stuff is valid. I have seen email addresses formatted this way, and while it is probably not very common, and I personally have serious issues with non-standard characters like spaces etc. in names of things, there are systems that for whatever historical or backward compatible purpose do use these unconventional formats.
While I don't consider this a critical issue, since the email addresses I saw formatted like this came back undeliverable, usually because some mail system along the way did not handle them properly and corrupted the email address, I am mentioning it just in case you would like your product to be robust enough to handle them. It would have saved me some time.