More upgrade stuff Microsoft Dynamics GP 2015–Version Checks & Upgrades
Microsoft Dynamics GP 2015–Version Checks & Upgrades – Microsoft Dynamics GP Community
Install, Upgrade & AdminPayables & ReceivablesMicrosoft & the GP EcosystemGP 2015
Archived post from 2015. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.