Windows Azure Backup problem

I installed Windows Azure Online Backup agent on or around July 1.

1. It completed a series of successful backups twice a day until August 7/19/2013
2. It started reporting "The Operation failed because Windows Azure Backup Agent was unable to contact the Windows Azure Backup...."
3. I turned off all firewall rules on the server and router
4. Uninstalled, re-downloaded and reinstalled Windows Azure Backup Agent
5. Was able to successfully ping and do trace to Windows Azure Backup
6. Eventually out of desperation created a new Backup Vault on Azure
7. Everything started to work perfectly and on the first backup 26 GB was uploaded
8. It completed a series of successful backups twice a day until 8/5/2013 when it started to fail again
9. I changed to the original backup vault and partial backup did happen around 12 GB

The confusing part is that when a brand new vault was created everything works and then eventually it fails.

Any suggestion is appreciated.