Upgrade ZCS 4.0 to ZCS 5

[SiteDiscovery]

I have been doing some reading and I am under the impression that I cannot simply update from v4.0 to V5.0. I have to update to V4.5 first.

Aside from a bunch of backups, what should I be aware of going from 4.0 to 4.5? Will I lose my user accounts? Do I need to backup and restore all users e-mail or will it leave it alone. Also, should I just jump from 4.0 to 4.5.11 or should I start at 4.5.8 or something and update from there?

Links to any wiki pages to read would be great!

CENTOS 4 / RHEL 4
Zimbra Open Source edition 4.0

Thanks!!

[soxfan]

I don't have any wiki or forum links that you are looking for at this point, but I can tell you that you should be able to upgrade from 4.0 --> 4.5 --> 5.0 without losing any accounts or email messages. I'm pretty sure you are correct in saying that you can't go directly from 4.0 to 5.0. The only thing I'm not sure of is the 4.5.x upgrade. I know there was issue in the 4.5.7/4.5.8 range, but I'm not sure what would happen if you try going directly from 4.0 to say 4.5.11.