Question:
Is it possible to read unread email from a POP3 server?
Answer:
The POP3 protocol does not provide anything that allows the client to download "unread" email. Pure-POP3 servers do not store read/unread status information
on the server. The only way a program can read "unread" email is to save the read/unread status of each email locally. This can be done by keeping a file of UIDLs that are on the server and have already been read.
The POP3 protocol provides a command to download the complete set of UIDLs for all email in a mailbox, so the "unread" emails are those UIDLs on the POP3 server that are not present in your local UIDL file. You may then download
the complete emails or email headers for only those emails that have not yet been read. An example in the Ruby scripting language is available here:
Ruby Script to Download Unread Email from POP3 Server.
Note: The Chilkat Email API is the same across all programming languages: C#, C++, VB6, VB.NET, Delphi, Perl, Java, Python, Ruby, etc.
