1 - Create an Archive with reports, media and accounts of all companies on the current Server that is using Spire 3.6 or higher
2 - Download the Archive(s) file to your Downloads folder or some other folder that your Internet Browser will have access to, by clicking on the Archive file in Spire Server Admin
3 - Create a Snapshot of all companies (not mandatory for servers that are using Spire 3.6 or higher, but it is good insurance)
4 - Install Spire Server on the new server using the installation steps in the Spire online manual
5 - Import the Archive(s) stored in Step 2 or the Restore the snapshots created in Step 3, on the new server
6 - Uninstall Spire Server from the original server
7 - Once the clients has been working on the new server for a few days, delete C:\ProgramData\Spire on the old server