What does the POP3 CAPA UIDL command do?

pop3

Solution

The UIDL capability indicates that the optional UIDL command is supported.

POP3 servers may assign a unique number to each incoming mail message. This allows mail to be left on the server after it has been downloaded to the user. Both the mail client and the POP server must support this feature.

Problem

What does the POP3 CAPA UIDL command do?

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