[CalendarServer-users] exceptions.IOError: [Errno 13] Permission denied: '.../twisted/plugins/dropin.cache.new'

John Murdie john at cs.york.ac.uk
Wed Apr 7 07:42:01 PDT 2010

I'd successfully run Calendar Server 2.3 on an initial test machine
which had an install directory writeable by user 'calendar' - in whose
name the caldavd process was run. When I made an install of 2.4 on a
beta test machine for which the install directory was not writeable by
calendar, I saw the message:

exceptions.IOError: [Errno 13] Permission denied: '.../twisted/plugins/dropin.cache.new'

(I've elided the actual directory path, as it is not relevant.)

The problem is apparently one known in Twisted 8.2.0, which is the basis
of the version provided for use with 2.4. See
http://twistedmatrix.com/documents/current/core/howto/plugin.html for
the background, but I think that the problem is long since fixed in
newer versions of Twisted.

I worked around the problem by running 2.4 on the initial test system
where the install filesystem was writeable before returning to the beta
test install.

This problem will presumably go away when Calendar Server comes with an
up-to-date version of Twisted?

John A. Murdie

More information about the calendarserver-users mailing list