I had to reset my phone over suspicious behavior. Either some bug has surfaced, or my telephone was broken into, but the camera started to say that it is “in use by another program”. To avoid unnecessary doubts, I simply erased the whole thing and started all over.
I can do that because my contacts are synchronized to DAV server using CardDAV-Sync free address book synchronization tool. It works well and synchronizes my contacts fairly well. When I need to start all over, I install it again and it pulls my contacts from the server. Nice.
This time, I set it up as usual and it synchronized, apparently, at least it did something for a long time… but no contacts appeared in the address book. Well, so I deleted the CardDAV-Sync, reinstalled it and configured again, with the same result half an hour later.
So, now I went to the server to check the logs. Everything looked normal, no errors. Reconfigured it all again, restarted the sync and watched in amazement how the phone pulled the address records but they were not appearing in the address book. After a very long search on the Internet and desperate walk through all possible and impossible settings in the phone I finally found what the problem was.
Address book has a filter accessible through Settings->Filter in the Address Book. Somehow, the filter was set not to show the entries from the CardDAV account. Once I switched on the contacts filter for the CardDAV, the address book was there. Several hours filled with desperation over a simple setting that got set wrong. But, next time I’ll know where to look.