leaving mail on server in high sierra
I am running a Mac Mini with 10.13.3
My mail is set up as Imap with Time warner
my wifes computer (windows 7, outlook for mail) cannot find recent mail after I read them.
There used to be a check box to leave messages on server, but it is gone in HS.
What am I missing (besides a clue)?
Mac mini, macOS High Sierra (10.13.3)