Reading Time: 3 minutes If you are are planning to upgrade your Horizon Connection Server’s OS, there are two different paths. One is using an in-place upgrade of Windows Server that can work (in theory). The second one is decommisioning your connection server and replace with a new one (and repeat if you have more). The strategy really depends of the size of your environment and how much is production critical. With a dev or lab environment single server, the in-place OS upgrade could make sense.