Getting this error from my server code which uses boto to interace with Dynamo

   [Mon Feb 16 07:25:22 2015] [error] JSONResponseError: JSONResponseError: 400 Bad Request
   [Mon Feb 16 07:25:22 2015] [error] {u'message': u'Signature expired: 20150216T072522Z is now earlier than 20150216T07252
   2Z (20150216T074022Z - 15 min.)', u'__type': u'com.amazon.coral.service#InvalidSignatureException'}

The server is a Window Server 2012 Standard box

Reboot the box fixed the problem