[Evolution] Google Calendars are read-only

[Michael Seifert <michseif web de>]

Hello everybody,

I have a strange problem with Evolution (3.6.4 on Arch Linux, but the
problem existed already in some of the earlier versions). On my laptop,
I've added two Google calendars. For both of them, I am not allowed to
edit existing or create new tasks, input window is mostly greyed out and
a message tells me that the calendar is read-only. Removing a calendar
and adding it again allows for a temporary fix of the problem, but after
next reboot it reoccurs.

The most strange part of the story: On my desktop PC I use the same
calendars and basically the same setup of Evolution (also the same
version, same OS) and I never had such problems there. 

What could I do to find the cause of this stupid issue or, at best, to
fix it?
Thanks, Michael