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From version 8.5.12G onwards NMIS ships with a model upgrade tool and the installer offers to run it for you. If you are using NMIS 8.5.10G you can download the upgrade tool here; it is recommended that you save it as /usr/local/nmis8/admin/modelupgrade_upgrademodels.pl.
Please note that the model upgrade tool is version-specific and will not work with NMIS releases other than the one it was shipped with. The current version for 8.5.10G handles model upgrades from any 8.5.X and 8.4.X versions to 8.5.10G.
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