I recently (10 days ago) upgraded from 12.3 to 13.1 by doing afresh install & preserving the /home folders. Since then korganizer hasn't worked.

Symptoms:
1) existing calendar entries weren't displayed
2) Akunambol (for sync with onemediahub) had a strange entry for the sync local source for events & tasks & no other choices
3) new entries didn't sync via akunambol (didn't show in logs) and didn't show on onemediahub (ex-funambol)

I deleted the local calendar in kpim and created a new one (file, ical format). After that:
A) akunambol could now be configured with the newly created calendar file
B) forced sync back to client (desktop machine) showed in logs the entries created, but nothing visible in korganizer
C) new entries don't sync back to onemediahub (not showing in log or appearing in server)
D) the panel widgets display the task & event entries
E) the calendar is 'ticked' as active in korganizer & is the only calendar source

kmail works perfectly, as does kontact.
all worked properly before install of 13.1

I have 13.1 fully updated.

Any advice on how to trace fault / how to fix?

Thanks
David

Versions:
akonadi-4.11.5-464.1.x86_64
akonadi-runtime-1.10.3-7.1.x86_64
akunambol-0.2.70.git.1387591463-2.2.x86_64
kdepim4-4.11.5-464.1.x86_64
kdepim4-runtime-4.11.5-457.1.x86_64
kdepimlibs4-4.11.5-478.4.x86_64
kmail-4.11.5-464.1.x86_64
kontact-4.11.5-464.1.x86_64
korganizer-4.11.5-464.1.x86_64
libakonadi4-4.11.5-478.4.x86_64
libakonadiprotocolinternals1-1.10.3-7.1.x86_64
libakunambolprivate4-0.2.70.git.1387591463-2.2.x86_64
libkdepim4-4.11.5-464.1.x86_64
libkdepimlibs4-4.11.5-478.4.x86_64
plasma-addons-akonadi-4.11.5-318.2.x86_64
plasmoid-akonadi-calendars-0.2.2-1.4.x86_64
plasmoid-akonadi-tasks-0.1.3-1.6.x86_64