HEAT upgrade in System Configuration Wizard fails with error 'the underlying connection was closed'

Version 1

    Details

    When trying to upgrade  the configdb the customer is getting an error 

    "Failed to apply patch to the tenant ConfigDB: The underlying connection was closed: The connection was closed unexpectedly.
    The ApplyPatchHEATSM2015.1.1.log in C:\Logs\ReleaseTool lists the following message:
    "proxy authentication required"

     


    Resolution

    To complete the upgrade the proxy settings were temporarily disabled:


    Go to Internet Explorer > Tools > Internet Options > LAN Settings:
    Check 'Bypass proxy server for local addresses'