Calendar Doesn't Work after Server 5.0.4 Migration

After upgrading from server 4.x to 5.0.4, I am able to turn calendar "on" in the server app, but it does not allow connections.

Running sudo /Applications/Server.app/Contents/ServerRoot/usr/sbin/calendarserver_diagnose gives the following message:

Traceback (most recent call last):

File "/Applications/Server.app/Contents/ServerRoot/usr/sbin/calendarserver_diagnose" , line 8, in <module>

from pkg_resources import load_entry_point

File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/pkg_resources/__init__.py", line 3074, in <module>

@_call_aside

File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/pkg_resources/__init__.py", line 3060, in _call_aside

f(*args, **kwargs)

File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/pkg_resources/__init__.py", line 3087, in _initialize_master_working_set

working_set = WorkingSet._build_master()

File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/pkg_resources/__init__.py", line 645, in _build_master

ws.require(__requires__)

File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/pkg_resources/__init__.py", line 946, in require

needed = self.resolve(parse_requirements(requirements))

File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/pkg_resources/__init__.py", line 833, in resolve

raise DistributionNotFound(req, requirers)

pkg_resources.DistributionNotFound: The 'xattr' distribution was not found and is required by CalendarServer

Also, error.log has the following entries corresponding to turning on the calendar service:

2015-10-10 09:31:29-0700 [-] Log opened.

2015-10-10 09:31:29-0700 [-] [twisted.application.app#info] twistd 15.2.1 (/System/Library/Frameworks/Python.framework/Versions/2.7/Resources/Python.app/ Contents/MacOS/Python 2.7.10) starting up.

2015-10-10 09:31:29-0700 [-] [twisted.application.app#info] reactor class: twisted.internet.kqreactor.KQueueReactor.

2015-10-10 09:31:29-0700 [-] ControlSocket starting on '/var/run/caldavd/caldavd.sock'

2015-10-10 09:31:29-0700 [-] Traceback (most recent call last):

2015-10-10 09:31:29-0700 [-] File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/bin/twistd ", line 17, in <module>

2015-10-10 09:31:29-0700 [-] run()

2015-10-10 09:31:29-0700 [-] File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/twisted/scripts/twistd.py", line 27, in run

2015-10-10 09:31:29-0700 [-] app.run(runApp, ServerOptions)

2015-10-10 09:31:29-0700 [-] File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/twisted/application/app.py", line 657, in run

2015-10-10 09:31:29-0700 [-] runApp(config)

2015-10-10 09:31:29-0700 [-] File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/twisted/scripts/twistd.py", line 23, in runApp

2015-10-10 09:31:29-0700 [-] _SomeApplicationRunner(config).run()

2015-10-10 09:31:29-0700 [-] File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/twisted/application/app.py", line 393, in run

2015-10-10 09:31:29-0700 [-] self.postApplication()

2015-10-10 09:31:29-0700 [-] File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/twisted/scripts/_twistd_unix.py", line 193, in postApplication

2015-10-10 09:31:29-0700 [-] self.startApplication(self.application)

2015-10-10 09:31:29-0700 [-] File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/twisted/scripts/_twistd_unix.py", line 381, in startApplication

2015-10-10 09:31:29-0700 [-] service.IService(application).privilegedStartService()

2015-10-10 09:31:29-0700 [-] File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/twisted/application/service.py", line 275, in privilegedStartService

2015-10-10 09:31:29-0700 [-] service.privilegedStartService()

2015-10-10 09:31:29-0700 [-] File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/twisted/application/service.py", line 275, in privilegedStartService

2015-10-10 09:31:29-0700 [-] service.privilegedStartService()

2015-10-10 09:31:29-0700 [-] File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/calendarserver/tap/caldav.py", line 481, in privilegedStartService

2015-10-10 09:31:29-0700 [-] super(GroupOwnedUNIXServer, self).privilegedStartService()

2015-10-10 09:31:29-0700 [-] File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/twisted/application/internet.py", line 103, in privilegedStartService

2015-10-10 09:31:29-0700 [-] self._port = self._getPort()

2015-10-10 09:31:29-0700 [-] File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/twisted/application/internet.py", line 131, in _getPort

2015-10-10 09:31:29-0700 [-] 'listen%s' % (self.method,))(*self.args, **self.kwargs)

2015-10-10 09:31:29-0700 [-] File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/twisted/internet/posixbase.py", line 405, in listenUNIX

2015-10-10 09:31:29-0700 [-] p.startListening()

2015-10-10 09:31:29-0700 [-] File "/Applications/Server.app/Contents/ServerRoot/Library/CalendarServer/lib/python 2.7/site-packages/twisted/internet/unix.py", line 302, in startListening

2015-10-10 09:31:29-0700 [-] raise CannotListenError, (None, self.port, le)

2015-10-10 09:31:29-0700 [-] twisted.internet.error.CannotListenError: Couldn't listen on any:/var/run/caldavd/caldavd.sock: [Errno 48] Address already in use.

Can anyone help? Again, from the server app there is no indication that calendar isn't working; I just cannot connect to it.