Specifies that Google Update should roll installations of Google Talk Plugin (Voice and Video Chat) back to the version indicated by "Target version prefix override".
This policy setting has no effect unless "Target version prefix override" is set.
If this policy is not configured or is disabled, installs that have a version higher than that specified by "Target version prefix override" will be left as-is.
If this policy is enabled, installs that have a version higher than that specified by "Target version prefix override" will be downgraded to the highest available version that matches the target version.
This policy is meant to serve as temporary measure when Enterprise Administrators need to downgrade for business reasons. To ensure users are protected by the latest security updates, the most recent version should be used. When versions are downgraded to older versions, there could be incompatibilities.
This policy is available only on Windows instances that are joined to a Microsoft® Active Directory® domain.