Restrict Use of Salesforce Classic HTML-Based Email Templates to Secure Browsers (Previously Released Critical Update)

As announced in Summer ’18, this critical update prevents using HTML-based email templates, such as custom, Visualforce, or standard HTML templates, from Microsoft Internet Explorer. Internet Explorer doesn’t support the Salesforce Content Security Policy (CSP), so it can’t provide the required browser protection. We recommend that you use a browser with CSP support, such as Microsoft Edge, Google Chrome, or Mozilla Firefox.

Where: This change applies to Salesforce Classic in all editions, except Personal Edition.

When: This critical update is enforced in the Winter ’20 release.

How: Although we recommend not using Internet Explorer for HTML-based templates, you can override this restriction. In Setup, under Session Settings, select Override Restriction for Accessing HTML-Based Email Templates in Salesforce Classic Using Internet Explorer.