Take a look at /opt/zimbra/logs/mailbox.log and search for 500 errors.
However a few years ago I had a similar problem, it was caused by wrong ownership of the logos files. I solved running as root /opt/zimbra/libexec/zmfixperms .

Yes, you can remove Zextras trial after importing the backup. The migration process is free.

Hi, since you have Zimbra Open Source edition, follow this wiki: https://wiki.zextras.com/wiki/ZeXtras_M ... Tool_Guide

Since the parameters normally involved in these problems (zimbraFileUploadMaxSize, zimbraImapMaxRequestSize,zimbraMailContentMaxSize, zimbraMtaMaxMessageSize) are configurable either at globalConfig or server level, did you check that the parameters did correctly propagate to the new server, too?

Hi, follow this wiki article: https://wiki.zimbra.com/wiki/Steps_To_R ... ZCS_Server

You can download the .ics file corrisponding to the calendar of your resources, then analyze it. Take a look here https://wiki.zimbra.com/wiki/Accessing_ ... d_Calendar to get some ideas about accessing calendars from remote.

Take a look here viewtopic.php?f=15&t=66234

Before posting, please take a look at "Recent topic" section that is on the homepage of these forums. In the last days everyone is opening a new topic about the same problem.

gabrieles wrote:
...
Users are still using the legacy backups? Let's remove them completely in the next version.
And all the subsystem connected to them, like the zmmboxmove, the zmblobchk...? Ah, true..
...

That is alarming No more rolling updates then

Probably you have an unpatched version of Zimbra. Take a look here viewtopic.php?f=15&t=65932 and here https://lorenzo.mile.si/zimbra-cve-2019 ... ction/961/ to have some guidance.

Hello roger_m,
take a look at the free Zextras migration tool to perform Zimbra upgrades, it simplifies a lot the upgrade procedure: https://wiki.zextras.com/wiki/Migrate_Zimbra