Internal error at startup

Getting this error message when opening a project in bazaar explorer:

bzr: ERROR: exceptions.ValueError: need more than 1 value to unpack

Traceback (most recent call last):
  File "C:/Program Files (x86)/Bazaar/plugins\explorer\lib\explorer.py", line 1524, in callable_with_cleanup
  File "C:/Program Files (x86)/Bazaar/plugins\explorer\lib\explorer.py", line 1691, in _open_location_task
  File "C:/Program Files (x86)/Bazaar/plugins\explorer\lib\location_viewer.py", line 163, in add_location
  File "C:/Program Files (x86)/Bazaar/plugins\explorer\lib\location.py", line 178, in view
  File "C:/Program Files (x86)/Bazaar/plugins\explorer\lib\view_workingtree.py", line 94, in ui
  File "C:/Program Files (x86)/Bazaar/plugins\explorer\lib\html_report_view.py", line 51, in ui
  File "C:/Program Files (x86)/Bazaar/plugins\explorer\lib\html_report_view.py", line 56, in refresh_view
  File "C:/Program Files (x86)/Bazaar/plugins\explorer\lib\view_workingtree.py", line 153, in report_text
  File "C:/Program Files (x86)/Bazaar/plugins\explorer\lib\status_report.py", line 196, in __init__
  File "C:/Program Files (x86)/Bazaar/plugins\explorer\lib\status_report.py", line 213, in _collect_data
  File "C:/Program Files (x86)/Bazaar/plugins\explorer\lib\status_data.py", line 44, in get_status_info
  File "bzrlib\branch.pyo", line 1022, in last_revision
  File "bzrlib\decorators.pyo", line 155, in read_locked
  File "bzrlib\branch.pyo", line 1031, in last_revision_info
  File "bzrlib\branch.pyo", line 2664, in _read_last_revision_info
ValueError: need more than 1 value to unpack

bzr 2.6b1 on python 2.6.6 (win32)
arguments: ['C:\\Program Files (x86)\\Bazaar\\bzrw.exe', 'explorer']
encoding: 'cp1252', fsenc: 'mbcs', lang: None
plugins:
  bzrtools C:\Program Files (x86)\Bazaar\plugins\bzrtools [2.5.0]
  changelog_merge C:\Program Files (x86)\Bazaar\plugins\changelog_merge [2.6b1]
  colo C:\Program Files (x86)\Bazaar\plugins\colo [0.4.0]
  explorer C:\Program Files (x86)\Bazaar\plugins\explorer [1.3.0dev]
  fastimport C:\Program Files (x86)\Bazaar\plugins\fastimport [0.14.0dev]
  git C:\Program Files (x86)\Bazaar\plugins\git [0.6.8dev]
  launchpad C:\Program Files (x86)\Bazaar\plugins\launchpad [2.6b1]
  loom C:\Program Files (x86)\Bazaar\plugins\loom [2.3.0dev]
  netrc_credential_store C:\Program Files (x86)\Bazaar\plugins\netrc_credential_store [2.6b1]
  news_merge C:\Program Files (x86)\Bazaar\plugins\news_merge [2.6b1]
  pipeline C:\Program Files (x86)\Bazaar\plugins\pipeline [1.4.0]
  qbzr C:\Program Files (x86)\Bazaar\plugins\qbzr [0.23.0dev]
  rewrite C:\Program Files (x86)\Bazaar\plugins\rewrite [0.6.4dev]
  svn C:\Program Files (x86)\Bazaar\plugins\svn [1.2.2dev]
  upload C:\Program Files (x86)\Bazaar\plugins\upload [1.2.0dev]
  xmloutput C:\Program Files (x86)\Bazaar\plugins\xmloutput [0.8.8]

***

Getting this error message when running bzr commands via cmd.exe:

bzr: ERROR: exceptions.ValueError: need more than 1 value to unpack

Traceback (most recent call last):
  File "bzrlib\commands.pyo", line 930, in exception_to_return_code
  File "bzrlib\commands.pyo", line 1141, in run_bzr
  File "bzrlib\commands.pyo", line 673, in run_argv_aliases
  File "bzrlib\commands.pyo", line 697, in run
  File "bzrlib\cleanup.pyo", line 136, in run_simple
  File "bzrlib\cleanup.pyo", line 166, in _do_with_cleanups
  File "bzrlib\commands.pyo", line 1158, in ignore_pipe
  File "bzrlib\builtins.pyo", line 414, in run
  File "bzrlib\status.pyo", line 140, in show_tree_status
  File "bzrlib\branch.pyo", line 1022, in last_revision
  File "bzrlib\decorators.pyo", line 155, in read_locked
  File "bzrlib\branch.pyo", line 1031, in last_revision_info
  File "bzrlib\branch.pyo", line 2664, in _read_last_revision_info
ValueError: need more than 1 value to unpack

bzr 2.6b1 on python 2.6.6 (Windows-post2008Server-6.2.9200)
arguments: ['bzr', 'status']
plugins: bzrtools[2.5.0], changelog_merge[2.6b1], colo[0.4.0],
    explorer[1.3.0dev], fastimport[0.14.0dev], git[0.6.8dev],
    launchpad[2.6b1], loom[2.3.0dev], netrc_credential_store[2.6b1],
    news_merge[2.6b1], pipeline[1.4.0], qbzr[0.23.0dev], rewrite[0.6.4dev],
    svn[1.2.2dev], upload[1.2.0dev], xmloutput[0.8.8]
encoding: 'cp1252', fsenc: 'mbcs', lang: None

*** 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.