Unable to delete a To-do item.

I’ve never really used the To-do, so I can tell when it stopped working, I only noticed after today’s upgrade to 8.4.6. My problem is that I have one, and only one, list on my To-do-list, and I can delete it, I also can’t add new items to to-do-list. When I try to delete it it just says “You have insufficient privileges to delete items in this folder.”, the error-message kind of says it all, but I can’t understand why, and I can understand how to fix it. Any tips?
We are on Debian 8.10with Kopano 8.4.6.

To-Do List is a search folder, so perhaps k-search has some useful logs…

Good idea, in the log I see this:
search - WARNING - could not connect to server at ‘default:’, retrying in 5 sec

And init.d/kopano-search status says
feb. 21 09:22:29 mail kopano-search[504]: [error ] gsoap connect: ()
feb. 21 09:22:29 mail kopano-search[504]: [error ] virtual HRESULT M4LMsgServiceAdmin::ConfigureMsgService(const MAPIUID*, ULONG_PTR, ULONG, ULONG, const SPropValue*): MSGSer…r (80040115)