If facing the issue "Failed to establish connection with server" while logging in SBO then you have to check whether software administrator is stopped or not by going to following path :
Windows/All Programs/SchneiderElectricStruxureWare/BuildingOperation/SoftwareAdministartion
Click on the start button. It will start the server and you will be able to login.
Windows/All Programs/SchneiderElectricStruxureWare/BuildingOperation/SoftwareAdministartion
Click on the start button. It will start the server and you will be able to login.