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Running the VSA 5.1 scripted installer (install.exe) against a VSA 1.0 cluster is not supported (2036630)
Note: The scripted installer is designed for greenfield or fresh installs only.
While it is extremely unlikely that you have a VSA 1.0 cluster with no registered virtual machines, the behavior of the scripted installer presents the potential for data loss. The loss of data would apply to unregistered virtual machines still present on the datastore and other non-virtual machine related files such as CD/DVD image files (like ISO files).
A revised version of the scripted installer (Install.exe) will be posted in the form of a new VSA 5.1 ISO on the vmware.com download site as soon as it is available, which will automatically detect if an existing VSA 1.0 cluster is installed and error out immediately instead of making changes to the cluster.
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