Error Connecting to Outlook via COM

I have the following python code

o = win32com.client.Dispatch("Outlook.Application")
ns = o.GetNamespace("MAPI")
profile = ns.Folders.Item("Profile Name")
tasks = profile.Folders.Item("Tasks")
print tasks.Items

When i run it, the script crashes with this error:

Traceback (most recent call last):
  File "start.py", line 47, in <module>
    o = win32com.client.Dispatch("Outlook.Application")
  File "C:\Python27\lib\site-packages\win32com\client\__init__.py", line 95, in Dispatch
    dispatch, userName = dynamic._GetGoodDispatchAndUserName(dispatch,userName,clsctx)
  File "C:\Python27\lib\site-packages\win32com\client\dynamic.py", line 108, in _GetGoodDispatchAndUserName
    return (_GetGoodDispatch(IDispatch, clsctx), userName)
  File "C:\Python27\lib\site-packages\win32com\client\dynamic.py", line 85, in _GetGoodDispatch
    IDispatch = pythoncom.CoCreateInstance(IDispatch, None, clsctx, pythoncom.IID_IDispatch)
pywintypes.com_error: (-2146959355, 'Server execution failed', None, None)

I also tried:

win32com.client.gencache.EnsureDispatch("Outlook.Application")

Not sure what to do and what the problem is

Update: This only happens if Outlook is running, but issuing getActiveObject crashes with 'Operation unavailable'