The Velocity Update Wizard must be used to update Velocity v3.6 SP3 (or higher) to Velocity v3.8.4 release.
The Velocity Update Wizard must be used to update an existing Velocity 3.8.3 6 (or higher) release to the version 3.8.4 release, instead of the Velocity Installer. The Update wizard will must be run ran on your licensed Velocity Server, then your Velocity Clients will automatically be updated.
Prerequisites
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