In this article, I’ll show you how to upgrade the latest WSP file to an existing file on Farm Solution in a few simple clicks. You can save the WSP file in any folder. Open SharePoint PowerShell and run it as administrator; then run the following script: Install-SPSolution -Identity -WebApplication -GACDeployment  For example: Update-SPSolution -Identity Bamboo.CalendarPlus.wsp -LiteralPath “C:UsersspinstallerDesktopHW20.R4.7.SP2016.SLBamboo.CalendarPlus.wspcabBamboo.CalendarPlus.wsp” -GACDeployment  Give it a moment, then go to Central Admin->System Settings->Manage Form Solutions. We can see the Bamboo.CalendarPlus.wsp file upgraded on it. Questions? Contact us!