title: Google Blogger API : AccessTokenRefreshError:invalid_grand message
body: <p>I am using google-python-client-api for Blogger API (Service Account - OAuth).</p>
  
  <p>This is my code (which is taken my tasks api <a href="http://code.google.com/p/google-api-python-client/source/browse/samples/service_account/tasks.py" rel="nofollow">example</a>)</p>
  
  <pre><code>import httplib2
  import pprint
  import sys
  
  from apiclient.discovery import build
  from oauth2client.client import SignedJwtAssertionCredentials
  
  f = file("privatekey.p12", "rb")
  key = f.read()
  f.close()
  
  credentials = SignedJwtAssertionCredentials(
      "2-abcdr@developer.gserviceaccount.com",
      key,
      scope = "https://www.googleapis.com/auth/blogger")
  
  http = httplib2.Http()
  http = credentials.authorize(http)
  
  service = build("blogger", "v3", http=http)
  </code></pre>
  
  <p>when I am running this code, its showing </p>
  
  <pre><code>Message File Name   Line    Position    
  Traceback               
      &lt;module&gt;    D:\Code\myScripts\py\gData.py   20      
      build   build\bdist.win32\egg\apiclient\discovery.py    191     
      new_request build\bdist.win32\egg\oauth2client\client.py    402     
      _refresh    build\bdist.win32\egg\oauth2client\client.py    569     
      _do_refresh_request build\bdist.win32\egg\oauth2client\client.py    625     
  AccessTokenRefreshError: invalid_grant      
  </code></pre>
  
  <p>What's the problem and how should I fix it??</p>
  
  <p>I even tried <code>tasks.py</code> example code.. and its even showing the same error</p>
  
  <p><em>I am very much sure that service account email address is right</em></p>