It's very helpful that Meinberg have provided an installer for the highly-respected and high-accurate NTP software for Windows users - my thanks to them. This Web page provides a quick guide to installing NTP on Windows XP, Vista, or Windows-7/8/10, using the standard out-of-the-box settings to sync your PC to the Internet, and then checking that you have a working installation. These notes show why you would want to use NTP as opposed to other timekeeping software. Some programs such as the excellent Plane Plotter even require that NTP be installed before you are allowed to use some of the more advanced features.
If you have more than one PC, you should install NTP as described below on each PC. If you have more than a few PCs you may want to create one local time server (locked to the Internet) for your network and sync the other PCs to that local server, by adding one line to the configuration file. More information is here. This is easy, because the software will work as both a client to a remote NTP server, and as a server to which other NTP clients can connect. For a rather low extra cost (US $35, £25) you can lock that local time server to GPS, making it far more precise than one locked to Internet sources. You might like to use something like a Raspberry Pi as a low-cost, stand-alone, precision time server.