ArcGIS Maps for SharePoint Configuration Page and/or Locate Workflow fails to connect over HTTPS, or returns error: “Unable to load https://<URL>/sharing/generateToken status: 500”

Error Message

If the ArcGIS Maps for SharePoint Configuration Page and/or Locate Workflow fails to connect over HTTPS, and returns the following error:

“Unable to load https://<URL>/sharing/generateToken status: 500”;

This may be due missing Windows Updates.

Cause

ArcGIS Maps for SharePoint leverages the Microsoft .NET framework SSL/TLS client libraries which, if sufficiently out of date, will fail to negotiate TLS 1.2 HTTPS handshakes required by ArcGIS Online and other secure/managed systems.

Solution or Workaround

Apply pending Windows Updates to all WFE (Web Front End) SharePoint servers.  Refer to the following article(s):

• Update to enable TLS 1.1 and TLS 1.2 as default secure protocols in WinHTTP in Windows

SharePoint 2010 Environments may also have to implement the following recommendations from Microsoft:

• Exchange Server TLS guidance Part 2: Enabling TLS 1.2 and Identifying Clients Not Using It