https://learn.microsoft.com/ru-ru/exchange/plan-and-deploy/post-installation-tasks/security-best-practices/exchange-download-domains?view=exchserver-2019 https://www.reddit.com/r/exchangeserver/comments/onhchg/download_domains_cve20211730_and_microsoft/?rdt=64153 https://www.alitajran.com/cve-2021-1730-vulnerability/ Your Exchange Server 2016/2019 is up to date with the latest Exchange Cumulative Update and Security Update. But when you check the Exchange Server health, it shows a security vulnerability is detected: Download Domains are not configured . This article will show how to configure Download Domains to address the CVE-2021-1730 vulnerability. Table of contents Vulnerability CVE-2021-1730 Check CVE-2021-1730 vulnerability status Configure Download Domains Step 1. Add download domain to internal DNS Step 2. Add download domain to external DNS Step 3. Add download domain to certificate Step 4. Add download domain to OWA virtual directory Step 5. Enable Dow...