- User Guide
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VNC Server must be licensed. If it is not, users cannot connect.
For more information on the different types of license available, to compare the remote control features provided by each, and to obtain a permanent or a trial license key, visit www.realvnc.com/products/vnc/licensing/.
You can apply a license key to VNC Server at any time.
You typically do this when you download and install VNC Server. You may subsequently do so in order to renew a support and upgrades contract.
1. Open the VNC Server shortcut menu. More on this menu.
2. Choose Licensing. The VNC Server - Licensing dialog opens.
3. Follow the instructions. Note you may additionally be prompted to configure VNC Server; see Harmonizing VNC Server for more information.
Note: If you do not have access to a graphical user interface when you need to apply a license key, use the vnclicense command line tool instead. For more information, run the command vnclicense -help from the directory in which VNC programs are installed.
When you apply a license key you may additionally be prompted to configure VNC Server. This is typically because your license key entitles you to fewer RealVNC® remote control features than VNC Server is currently configured to use. You must harmonize VNC Server with the license key.
For example, if at the end of a trial you choose to downgrade to VNC Server (Free), you must turn off encryption and system authentication. If you do not, users cannot connect.
Note that it is possible to run more than one instance of VNC Server on a computer (see Running multiple instances of VNC Server). If this is the case, you must harmonize all running instances separately. For example, if under UNIX/Linux you have five instances of VNC Server running, two in User Mode and three in Virtual Mode, and you apply the new license key to the licensing wizard of a particular instance of User Mode, then you must separately configure:
• The other instance of User Mode.
• All three instances of Virtual Mode.
Until you do, users will not be able to connect to these instances. Note that administrative privileges may be required to perform this operation if you are not the user who started VNC Server.
Understanding license scope
Under Windows, a VNC Server license key is system-wide. This means it applies to all users with accounts on the computer. Since only two instances of VNC Server can run concurrently on a Windows computer (one in Service Mode, and one in User Mode for the currently logged on user), this means that VNC Server is always licensed for all users.
Under UNIX/Linux and Mac OS X, however, there is another dimension to license scope. The license to use VNC Server not only applies to all computer users, but additionally limits the number of instances of VNC Server that can start. For example, if your license entitles you to five ‘desktops’, attempting to start VNC Server for a sixth time fails. For more information, visit www.realvnc.com/products/vnc/documentation/5.0/licensing-faq/.
Note: You can quickly see how many instances of VNC Server your license permits you to start, and how many of these are currently running. See page 80 for more information.
Note you can start a maximum of five instances of VNC Server (Free) on UNIX/Linux and Mac OS X computers. Upgrade the host computer to VNC Server (Enterprise) or VNC Server (Personal) if flexibility is important to you.