Start IIS and in the left menu, click Application pools.
In the list of application pools, right-click the Isah SCSN API AppPool and choose Stop.
If you fail to stop the service before updating, you will get a message during the update process that dotnet.exe is still running. The update can try to close the programs, but it does not have the necessary permissions for that, so that will not work. If you continue the update without shutting the AppPool off first, you will have to reboot your computer after the update process for the update to take effect.
To start the update double-click Isah.SupplyChain.Interface.Setup.msi and follow instructions. Data from the original installation will be pre-selected in every window.
After the update, go back to the IIS Application pools, right-click the Isah SCSN API AppPool and choose Start.