This depends on the RDP server implementation. On a Microsoft Windows PC only a single user can be signed in at a time and the following happens.

If the local user is signed in with the same user account, they will be logged out immediately and you will be connected. If they would sign in again, you will be disconnected. Your screen will then freeze and you'll see the message "The session within the upstream server has ended because it conflicts with another session. (521)"

If the local user is signed in with a different user account, you will see the following prompt.

If you select Yes to proceed, you will see the following screen.

The local user will then be presented with the following pop-up:

If they select OK or do not react within 30 seconds, you will connect. If they select Cancel, you will not connect and instead see the following.

This depends on the RDP server implementation. On a Microsoft Windows PC only a single user can be signed in at a time. Meaning you will connect and the already connected user will be disconnected. Their screen will freeze and they'll see the message "The session within the upstream server has ended because it conflicts with another session. (521)".

This depends on the RDP server implementation. On a Microsoft Windows PC only a single user can be signed in at a time. See the above questions for more in-depth details about what happens.

The screen size is determined by your browser window size when you open the RDP service. It is not rescaled afterwards when you change your browser window size. Make sure your browser window has the desired size when you open the RDP service.

The RDP protocol loads the same resolution as your own screen. In case of RDP StationAccess, it will load the resolution based on your browser window size the moment you opened RDP StationAccess. Meaning if your on-site computer is showing a fixed high resolution interface or image, you cannot use the RDP protocol to view everything on a small resolution screen. Try to reduce the on-site screen resolution or look for alternatives, like VNC EasyControl.

The machine's engineering station, e.g. the Microsoft Windows or Linux PC, is not running an RDP server. Make sure that an RDP server is installed and enabled. On Microsoft Windows it's installed by default, but not enabled by default. For detailed instructions on how to install and enable RDP on your operating system, either consult one of the many online guides or contact your IT administrator.

While you were connected, someone else connected remotely or signed in locally. As a result, your connection was disconnected. While it depends on the RDP server implementation on the machine's engineering station, e.g. the Microsoft Windows or Linux PC, typically RDP only supports 1 signed in user at a time.

Check the Event log on a Device page in the Portal to see who connected and contact them to make sure you don't interrupt each other. If no user connected after you, someone signed in locally.

The login username and password that are configured at the RDP service are incorrect. Make sure that the correct username and password to login to the machine's engineering station with RDP are entered at the RDP service in the Fleet Manager. If you're unsure, contact your IT administrator, or test the credentials locally, or test the credentials remotely by setting up a VPN connection and then starting an RDP connection from your computer to the engineering station.