I'm not sure why you have to put the port number. I don't think you should but if you have a look around the forum you'll find another similar post where this was the solution.
hmm... odd. Makes no sense to me (that a cert is required).
I'm not sure what you mean about the rest. Port 993 is used for secure IMAP so Roundcube needs to know the protocol to use (ssl/tls). PHP made certificate verification the default in the last few years. I can't remember exactly which version but its why there are the imap_conn_options so you can control that verification or disable it if you want want it.
Again, IMHO odd. I understand that port 993
doesn't tell RC whether it's
tls, or
ssl. But that would be a trivial task for
RC to determine on it's own. As to PHP making the change to require a cert; The box I'm testing this on, is only using version 5.6.
I can only imagine anyone
requiring a cert due to the elimination (depreciation) of the "NULL" cert by openssl, after the "heartbleed",
and similar vulnerabilities found in the openssl' implementation of SSL. But that wasn't even a year ago. I remember it well, as I maintain
some 200 ports for the *BSD
ports system. Many of which required modifications after the change.
Honestly; I'n not sure why
anyone would continue to use the openssl' implementation of SSL anymore. It was great in the 20th
century, but it really shows it's age, these days.
On the other hand; I have 2 other web-based mail clients I use, that happily communicate with Dovecot on port 993
without the
need to specifically state
ssl, or
tls. Nor do they require a cert, and
both of them are built on PHP.
I've still got some free(ish) time available. I've whipped up a port/mail/IMAP(s) tester built in PHP. At this point it tests whether the
MX/IMAP(s) communicate on the requested ports, and works well. I'm now going to attempt to add some "debugging" features to
it. So I can conclusively determine why RC won't work on port 993 w/o specifically adding an implementation,
and cert. While
other clients do.
Thank you very much for taking the time to respond, John!
--Chris