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.
ArcGIS Maps for SharePoint leverages the Microsoft .NET framework SSL/TLS client libraries which, if sufficiently out of date, will fail to negotiate TLS 1.2 HTTPS handshakes required by ArcGIS Online and other secure/managed systems.
Apply pending Windows Updates to all WFE (Web Front End) SharePoint servers. Refer to the following article(s):
SharePoint 2010 Environments may also have to implement the following recommendations from Microsoft: