I'm getting an error while getting subject of email

Question

This is subject im getting:
Please purchase Mail.dll license at https://www.limilabs.com/mail

this is the code

List<long> uidList = imap.Search(Flag.Unflagged);
List<MessageInfo> infos = imap.GetMessageInfoByUID(uidList);

Answer 1

You need to purchase a license, it's not expensive:
https://www.limilabs.com/mail/purchase