I recently had to remove and reinstall Roundcube from a linux email server and a number of program features broke. I found a #roundcube channel on IRC freenode and posted a question to the people there. I used the free HexChat software to connect to IRC.

A user’s address book, identities, and signatures disappeared from their web interface for Roundcube after the software was removed and reinstalled. I could still see all the data in the database, but it was disconnected. Thanks to sadsnork who ran into this issue before, I was able to fix the software. Turns out it was related to a different change. I had to modify the /etc/hosts file for another reason. I added an entry to force the server’s own DNS name to point to 127.0.0.1 for another software project. My change to the hosts file triggered roundcube to start storing the mail_host field in the database with the actual server name instead of localhost.

Whether you run the SQL from the command line or phpMyAdmin, this is what fixed the entries in the database.

First delete any NEW entries with the wrong information. Then run this update command to reset existing entries to the new name. Replace everything in the single quotes, i.e. [new entry] and [old entry], with your actual database data you want modified.

mysql> update users set mail_host='[new entry]' where mail_host='[old entry]';

Here is the tutorial on how to fix this problem in the roundcube database.

https://snork.ca/posts/2013-11-16-the-disappearing-roundcube-address-book/

The original post is here:

http://geroyblog.blogspot.com/2013/06/roundcube-missing-contacts-after.html