bzr: ERROR: bzrlib.errors.NoSuchRevision: CHKInventoryRepository('file://Server/WADIA%20%28W%29/RD%20%28R%29/Code/.bzr/repository/') has no revision null:

Traceback (most recent call last):
  File "bzrlib\commands.pyo", line 853, in exception_to_return_code
  File "bzrlib\commands.pyo", line 1055, in run_bzr
  File "bzrlib\commands.pyo", line 661, in run_argv_aliases
  File "bzrlib\commands.pyo", line 665, in run_direct
  File "bzrlib\cleanup.pyo", line 122, in run_simple
  File "bzrlib\cleanup.pyo", line 156, in _do_with_cleanups
  File "bzrlib\commands.pyo", line 1070, in ignore_pipe
  File "C:/Program Files/Bazaar/plugins\bzrtools\heads.py", line 101, in run
  File "bzrlib\decorators.pyo", line 140, in read_locked
  File "bzrlib\repository.pyo", line 1865, in get_revisions
  File "bzrlib\decorators.pyo", line 140, in read_locked
  File "bzrlib\repository.pyo", line 1873, in _get_revisions
NoSuchRevision: CHKInventoryRepository('file://Server/WADIA%20%28W%29/RD%20%28R%29/Code/.bzr/repository/') has no revision null:

bzr 2.1.1 on python 2.5.4 (Windows-XP-5.1.2600-SP3)
arguments: ['bzr', 'heads', '--tips', 'file://Server/WADIA (W)/RD (R)/Code']
encoding: 'cp1252', fsenc: 'mbcs', lang: None
plugins:
  bzrtools             C:\Program Files\Bazaar\plugins\bzrtools [2.1.0]
  explorer             C:\Program Files\Bazaar\plugins\explorer [1.0.1]
  launchpad            C:\Program Files\Bazaar\plugins\launchpad [2.1.1]
  netrc_credential_store C:\Program Files\Bazaar\plugins\netrc_credential_store [2.1.1]
  news_merge           C:\Program Files\Bazaar\plugins\news_merge [2.1.1]
  qbzr                 C:\Program Files\Bazaar\plugins\qbzr [0.18.4]
  rebase               C:\Program Files\Bazaar\plugins\rebase [0.5.5]
  svn                  C:\Program Files\Bazaar\plugins\svn [1.0.2]
  upload               C:\Program Files\Bazaar\plugins\upload [1.0.0dev]
  xmloutput            C:\Program Files\Bazaar\plugins\xmloutput [0.8.7.dev]

*** Bazaar has encountered an internal error.  This probably indicates a
    bug in Bazaar.  You can help us fix it by filing a bug report at
        https://bugs.launchpad.net/bzr/+filebug
    including this traceback and a description of the problem.