Kerio Connect offers two versions of its Outlook Connector, KOC and KOFF. Why would you use one vs. the other?
I asked Kerio if they had a document that explained the differences. They did not, so I've put this together. I've not been able to check everything against running systems, so I can't be certain that this is absolutely accurate, but it's better than nothing and I will update it as I get new information.
First, why two versions?
That's a really good question that I do not have a good answer for. Apparently adding off-line features was difficult enough that the software people felt they needed to start fresh, and indeed there was a time when you'd see recommendations to use the original KOC to get around certain bugs or problems.
The expectation was that eventually there'd be only one version, but it has been five years and there still are two. It seems that KOC may have been frozen in its development track; for example it cannot be used with Outlook 2010 or Outlook 2013 and cannot run on Terminal Server.
Kerio tech support did say this:
KOFF is our primary connector now. KOC is mostly there for legacy versions
of Outlook, but is no longer developed to the extent that KOFF is.
I personally cannot think of a reason to recommend KOC over KOFF since
KOFF is the most up to date method of connectivity and as you have seen
in the release notes, it gets updates, fixes and new features added to it.
Offline Features apparently not in KOC
I took these from both the release notes and the current PDF manual. As noted above, these MAY not be accurate; corrections and notes will be appreciated. Leave them as a comment or send me email if you prefer.
I'd love to be able to install KOC to verify these assumptions, but I don't have an old version of Outlook to try it with.
Of course the most obvious difference is that KOC allows off-line use - as the manual explains:
MS Outlook can be switched to offline mode. This implies that you can manage your email items also from home or on your business trips. This means that your email can be managed even there where the Internet connection is too slow or there is no connection at all. After reconnection to the Internet (switching to online mode), KOFF synchronizes all changes with the mailserver and sends mail from Outbox.
Additionally, KOC uses HTTP(S), IMAP(S) and SMTP(S) where KOFF only uses HTTP(S). KOFF also maintains local cache files.
But there is much more. First, let's look at the things mentioned in Release Notes under the KOFF heading. My assumption is that if they don't mention KOC, the added feature only applies to KOFF:
I've edited Kerio's language for clarity and brevity - engineers don't always write well, especially when English is not their native language.
Create meeting requests in shared Calendar on behalf of the Calendar's owner.
Accept meeting requests in shared Inbox on behalf of Inbox owner when there are editor rights for the Calendar provided.
DbBackup: Command line tool that can shrink local cache files when needed.
Public Folders can be configured to not be synchronized completely.
Ability to set KOFF upgrade policy in Administration..
Settings of silent update and lose/coupled package version. (I am not sure what this refers to)
Added support of Outlook's confidential tag in mails.
Added support for mail merge in MS Word.
The administrator is informed about KOFF users without installed Updater Service. This is in the Warning log.
Support for Microsoft Outlook 2010 and 2013
Ability to NOT store password in configuration (user is asked for it on each startup).
KOFF logs to a single log file for each user.
Next, we'll look at two features mentioned in the KOFF section of the manual but not mentioned in the KOC section. Note that the KOFF section of the version 8.1 manual is 32 pages long; the KOC section is 36 and they are laid out quite differently, so everything here represents my best guess only..
Synchronization. KOFF can synchronize headers only for individual folders.
Search in message body rather than just headers
Again, this is likely to be incomplete and inaccurate! Corrections will be deeply appreciated!