If -all- you want is email, I'd go for Squirrelmail, or possibly RoundCube.
Squirrelmail is nice and easy, works fine as a primary email interface. But lacks any groupware features at all. Which kinda sucks if you are used to having integrated calendars etc. and is enough to make me reject Ssquirrelmail out-of-hand as a solution for my needs.
Roundcube appears to be a better mail client, but has the same flaw that it only does email.
Horde Sucks. Royally. Hugely, and I would urge you to avoid it at all costs.
Wonderful functionality, many features, good UI (in parts) which is still being developed? what's not to like?
Actually, the list that makes it worthless goes like this:
1) It's massive instability, default updates to (apparently unrelated) ports break Horde. PHP5.4 is not a supported platform for FreeBSD/Horde, you have to roll your system down to 5.3 (5.4 is currently being shoved down our faces by the ports team despite only being released recently and full of major regressions and bugs due to it's mutant Ninja developers who prefer 'leet features' to 'bugfixing')
2) It's massive size. (related to 1, above of course) over a hundred packages, plus another hundred as dependencies. All creaking and rubbing against each other.
3) It's lack of documentation. What little is available is confusingly formatted, frequently incomplete or worse, incorrect. There is no coverage to the general documentation, install guides contain stupidities such as telling you that the only way to configure the system is via the online configuration tool. Whilst ignoring the fact that configuration errors can prevent you using that tool to fix your configuration. And (apparently deliberately) refusing to document the configuration directives.
4) It is being funded and influenced by corporate interests and steered inexorqably towards being a huge, dedicated admin team required, corporate behemoth.
I'll stop typing and simply say that unless you have hundreds of hours of your personal time to waste on the horde. You will havbe a happier life if you avoid it. When running it is lovely, but are you prepared to make the huge initial investment, and commit to many evenings 'fixing' it in the future?
I have just lost 6 months of my life to this, it's latest screwup is incredible (On monday morning, about 11am, halfway through a normal usage session with no other activity on the server at all, no updates or modifications for weeks) it starts totally failing, http connections succeed, but absolutely no response is sent by the horde, not a single byte of data. Connections are just held open and never close until Apache times them out, not a single error in any log, anywhere. Not a single bit of help on the Horde documentation or website.
I made the decision last night to de install this bloated bit MS'esque rubbish and install Citadel.
And I'd like to propose that as a alternative. Check out Citadel.org. It's like the horde.. but less suckage.
