To upgrade from v2015:
[LAN]EarliestLegacyVersion = 7500.
Restart the servers after adding the parameter for the changes to take effect.
When doing an online upgrade from v7.50 to v2018 check that any pre-7.20 Alarm Save files are removed from the v2018 project folders (e.g. <project_cluster>_ALMSAVE.DAT and <project_cluster>_ALMINDEXSAVE.DAT).
Published June 2018