calendar server not working after time machine restore

I am running Mountain Lion (10.8.5) with OS X Server (2.2.2) to provide Calendar Services and VPN access to a handful of users. A recent hard drive failure in the system means that I have installed a new hard drive and restored the system from a Time Machine backup.

The restore went smoothly and the computer boots. OS X Server appears to be happy and is providing VPN services. Calendar Services is enabled and shows a green indicator in the OS X Server management application.

However, no clients that were previously working with the CalDAV server are able to connect after the restore. This is true for iPhone and BusyCal clients. These clients were able to connect to the CalDAV server before the restore.

Using a webbrowser to access the following two URLs results in a "Service Temporarily Unavailable" message:

• https://servername/webcal/
• https://servername:8443/principals/

Looking through the error log at /var/log/caldav/error.log I see a bunch of entries like the following:

2013-12-17 23:30:45-0800 [PooledMemCacheProtocol,client] Unhandled Error

Traceback (most recent call last):

File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/twi sted/internet/defer.py", line 397, in errback

self._startRunCallbacks(fail)

File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/twi sted/internet/defer.py", line 464, in _startRunCallbacks

self._runCallbacks()

File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/twi sted/internet/defer.py", line 551, in _runCallbacks

current.result = callback(current.result, *args, **kw)

File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/twi sted/internet/defer.py", line 1101, in gotResult

_inlineCallbacks(r, g, deferred)

--- <exception caught here> ---

File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/twi sted/internet/defer.py", line 1043, in _inlineCallbacks

result = result.throwExceptionIntoGenerator(g)

File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/twi sted/python/failure.py", line 382, in throwExceptionIntoGenerator

return g.throw(self.type, self.value, self.tb)

File "/Applications/Server.app/Contents/ServerRoot/usr/share/caldavd/lib/python/twis tedcaldav/upgrade.py", line 1053, in startService

yield updater.updateCache(fast=True)

File "/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/twi sted/internet/defer.py", line 1045, in _inlineCallbacks

result = g.send(result)

File "/Applications/Server.app/Contents/ServerRoot/usr/share/caldavd/lib/python/twis tedcaldav/directory/directory.py", line 735, in updateCache

previousMembers = pickle.loads(membershipsCacheFile.getContent())

exceptions.EOFError:

Does anyone have a suggestion for how to get CalDAV working again after this Time Machine Restore?

Thanks