Possibly, but unsupported. If your Zimbra 9 server enforces Modern Auth (OAuth 2.0), version 7.3.1 will fail. You need to downgrade the server’s auth mode to "Native" (not recommended for security).
For IT administrators managing legacy systems, or individual users who prefer the classic interface, finding and installing the correct older version is crucial. This article dives deep into what Zimbra Desktop 7.3.1 is, why you might need it, where to find it safely, how to install it on modern Windows versions (Windows 10/11), and the security trade-offs involved. Zimbra Desktop 7.3.1 Older Versions for Windows
They are only suitable for:
: This version notably deprecated support for Windows XP , as the underlying Nw.js engine no longer supported the legacy OS. Contemporary Challenges and Risks Possibly, but unsupported