Hi Robert,
Based on what you've shared, this doesn't appear to be related to your local environment or browser cache.
The official release notes list Windows Desktop App 2.53.923 (August 3, 2026) as the latest release, but the public download page is still advertising 2.52.919, and your observation that appcast.xml is still showing 2.51.916 suggests the update hasn't propagated to all distribution endpoints yet.
I would expect this to be a temporary publishing/CDN synchronization issue rather than anything wrong with your environment. If it doesn't update within the next several hours (or by tomorrow), it would be worth opening a Care case or having a Genesys employee raise it internally so the desktop app distribution endpoints can be checked.
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Tracy
Genesys
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