Online License Access for RelaxIS

To start off: Download the RelaxIS Online Installer

How to validate the downloaded file...
  • Digital signature is missing
  • Digital signature is not valid
  • Digital signature is not from rhd instruments GmbH & Co. KG
then don't execute the file, and download it again from If the problem persists, please contact us. Avoid using direct links from emails.

Installation Instructions


How it Works


RelaxIS needs to be internally decrypted before it can run. For this it needs to communicate with a hardware dongle. This is done over the internet with a server at rhd instruments.

The server blocks all connection attempts by default. Logging in with the RelaxIS Online Client tells the server to allow connections from your computer.


You will need to make sure, that the following requirements are fulfilled:

  • Permanent internet connection
  • Outgoing TCP and UDP connections on ports
    • 22350
    • 57342

You can test the ports using the following websites:

Port 22350
Port 57342

You should see a status page for each website. If the connection times out, your router or ISP does not allow the connection. Please contact your administrator or IT department for help.

Please note: The permanent connection is only required for the trial version.

All purchased licenses are per default shipped with a USB hardware dongle that enables RelaxIS to be used offline.
Optionally, the dongle can be shared in your local network.
The online-based license is still available for purchased licenses per user choice.

Notes about the RelaxIS Online Client

client client
  • The RelaxIS Online Client is a separate program from RelaxIS and can run independently, it is however most often started by the RelaxIS login screen. You can find the program symbol in the notification area.
  • By default, the Online Client will be disconnected and closed automatically when the last instance of RelaxIS/Circuit Simulator closes. This can be changed in the RelaxIS settings.
  • Please check the IP address in the topmost box. It has to be the public IP address your computer uses to connect to the Internet. If it is not, you won’t be able to start RelaxIS.
  • A red symbol signals a problem with the connection. You can check the connection log by clicking the Advanced button in the lower right corner for further information.
  • Here you can also run automated tests by clicking the "Run Tests" button.
  • Please note: Depending on your internet connection and/or geographic location, the startup time of RelaxIS may be longer than usual (up to a few minutes).
  • The client must stay connected while you are using RelaxIS. Please do not close the Online Client after connecting! Instead, you can minimize it to the notification area by clicking the minimize button.


The RelaxIS Online Client can run automated tests for common problems.
You can check the FAQs below, or contact us. Please include the test log as generated by the Online Client!
To run the tests, please do the following:
  • First, open the RelaxIS Online Client from the notification area or start menu
  • Then run the tests by 1. Disconnecting, 2. clicking Advanced, 3. clicking Run tests


The Online Client cannot connect successfully. Why?
Please click the Advanced button and check the log. It will tell if it is a connection or an authentication problem. In case of a connection problem, please check that your internet connection allows outbound connections on port 57342 ( Check). In case of an authentication problem, your license might have expired. Please contact rhd instruments.

I can connect successfully but RelaxIS does not start due to a missing license. Why?
(1) A common problem is, that your network blocks connections on port 22350. This port is required for talking to our license server. Please verify with your network administrator that you are able to use this port for outgoing communication.

(2) Please open a webbrowser on the computer you are using RelaxIS on and browse to the address http://localhost:22352. Use the menu to navigate to Configuration->Basic->Server Search List. Please make sure that the list contains the entry If it doesn't, please use the Add button to add the entry. Click the Apply button after adding the entry.

(3) If the website from step (2) does not show up, it means that the Codemeter Runtime was not installed correctly or could not be started. Please perform the following steps

  • First try and reinstall RelaxIS. Make sure you also perform the installation of Codemeter during the RelaxIS installation.
  • You can download a stand-alone version of the Codemeter Runtime from Wibu. Select the correct operating system and download and install the Codemeter User Runtime.
  • After all installations, Codemeter should run as a Windows Service. Please open Computer Management -> Services and Applications -> Services, and look for the Codemeter Runtime Server service. It should be running. If not, you can try and manually start it.

(4) Please check carefully, if the IP address entered in the Online Client is indeed your public IP. Sometimes you have both an IPv4 address (4 pairs of values from 0-255) and an IPv6 address (8 sets of 4 numbers/letters, separated by a colon). In this case the Online Client usually finds the IPv6 address. Try to enter the IPv4 address instead. Also please make sure, that it is not a local address (e.g. starting with 192.168.)!

(5) It can happen that the IP address of the dongle server changes. While the DNS entry for is adjusted automatically, the old IP address might still be buffered by your local CodeMeter Runtime to avoid slow DNS lookups. In this case, please restart the CodeMeter Runtime by either:

  • a) Restart your computer
  • b) Open the Windows Services dialog from the Computer Management and restart the Service "CodeMeter Runtime Server"

(6) You are using a RelaxIS version older than 3.0.7. Please download and install the latest version of RelaxIS with the link at the top of the page.

The client disconnected while RelaxIS is running, and now RelaxIS is frozen. What should I do?
After a while RelaxIS should display a warning dialog (see below) that informs you that the license is missing. RelaxIS may appear frozen for over a minute before the dialog shows up (due to timeouts)! You don't have to terminate the program e.g. via task manager. Please open the Online Client from the notification area and reconnect it. Once the connection to the license server is reestablished, please click Retry in the license-missing dialog.


Cookies are used to store information like your shopping cart. We do not use any tracking cookies. You can decline the storing of cookies, which are then subsequently deleted once you exit the browser. In this case, you will loose the stored information, e.g. your cart.