In November 2018, Esri Released the Following Information For This Update:
Esri is planning an important update to ArcGIS Online in February 2019 that is likely to affect all ArcGIS software and custom solutions, including partner solutions. Please ensure that you are familiar with TLS and how this change may impact you, your customers, and your solutions.
The following message was sent to the Esri user community last week. Please review this message and the information on the TLS support page. For additional information and questions visit the TLS FAQ and feedback Web Form.
Esri is committed to providing strong security for the ArcGIS platform by using the latest industry standards and best practices for security protocols. To meet these industry expectations, we are making an important update to ArcGIS Online in February 2019 that is likely to affect most ArcGIS software and custom solutions. With this change, we are enforcing the use of TLS (Transport Layer Security) version 1.2 only and will remove support for earlier TLS versions 1.0 and 1.1.
More details about Esri’s support for TLS, including patches and instructions for updating software, can be found by visiting support.esri.com/en/tls.
Who is affected?
Users of most ArcGIS software or custom solutions using Esri technology using content from ArcGIS Online may be affected by this planned update to TLS protocol v1.2.
Esri's Update to TLS 1.2 IS SUPPORTED by Mapfolio for ArcGIS
To verify if your web browser supports TLS 1.2, check with the SSL Labs website, HERE.
For information on implementing TLS 1.2 in your web browser, check this knowledge base article from DigiCert, HERE.