Problems launching Websites to multiple PC's with the same user account logged on

[School_Engineer]

Hi
Has anyone experienced / solved the issue where if you launch a website to a group of machines with the same user account signed in the browser & site only opens on one machine.
using 4.7.3 on the master and a mix of 4.7.2 & 3 on the clients (were all 4.7.2 but upgraded a few to test if the version difference was the problem (Its not))
Any Suggestions welcome

[tobydox]

How do you launch the websites? Using the context menu or using the global toolbar at the top?