I am retrieving emails from my email server using IMAPClient (Python), by checking for emails flagged with "\Recent". After the email has been read the email server automatically sets the email flag to "\Seen".
What I want to do is reset the email flag to "\Recent" so when I check the email directly on the server is still appears as unread.
What I'm finding is that IMAPClient is throwing an exception when I try to add the "\Recent" flag to an email using IMAPClient's "set_flag" definition. Adding any other flag works fine.
The IMAPClient documentation say's the Recent flag is read-only, but I was wondering if there is still a way to mark an email as un-read. 
From my understanding email software like Thunderbird allows you to set emails as un-read so I assume there must be a way to do it.
Thanks.
Disclaimer:  I'm familiar with IMAP but not Python-IMAPClient specifically.
Normally the 'seen' flag determines if an email summary will be shown normal or bold.
You should be able to reset the seen flag.  However the recent flag may not be under your direct control.  The imap server will set it if notices new messages arriving.
How to change email flag to Recent using IMAPClient