This article highlights the essential components of an NX license file and a quick overview of what needs to be done once a license file is received from Siemens.


To access your NX software, you must first enable your NX license. Without a license file or borrowing a license from a server that has an active license, NX cannot run. The license file lets you to run NX, prevents piracy, and enables the management of the user base within a customer site or network.

Siemens licensing is an outsourced application developed by Flexera Software, LLC. Many of the Siemens PLM products use it and include configuration and control programming contained in a single “tools” type dialog. More on this later.

Disclaimer: I don’t fully understand all parts of the licensing and proprietary code. However, the average user/administrator does not need to understand it completely. You only need to know how to successfully complete the installation and configuration.

How it starts

A customer can download the NX software, either from the Siemens website or from our Swoosh Customer Portal site at (you’ll need a Swoosh account):


Swoosh Portal


You cannot run the software only by downloading only the compressed installation file and unzipping it. The license file enables the software to run.

When a customer purchases NX, Siemens emails a 7-day temporary license file to the customer that shows two things:

  • The customer’s Webkey account number, an access code needed to access proprietary information on the Siemens website, such as GTAC help, the data upload/download site, etc.
  • The customer’s Sold-To, or Install ID, a 7-digit number assigned by Siemens to the customer’s purchase order for that NX software bundle. A single customer can have more than one Sold to number. Often, different locations/facilities have different Sold-To’s. If the customer switches providers or changes Siemens partners, they receive a different Sold-To.

The content in the seven-day temp license file resembles the permanent or annualized license file, but contains less information. This generic seven-day temp license file allows the software to run on any qualified device or computer. Salespeople often use this to allow a customer to try out the software before purchasing. You can also get temporary licenses for longer trial periods such as 30-days and longer. These temporary licenses contain an advisement that explains the limited enabling. You’ll need to register that specific computer information with Siemens…


This release requires a composite


Types of Licenses

Once Siemens sends the temporary license file, you must provide additional information about the environment and device(s) on which you plan on using the software, in accordance with the specific type of licensing purchased. Different types of licenses provide a wide diversity of options that suit customer requirements and affordability:

  • Fixed node – license file contains dedicated data content that only allows the software to run on one specific computer or device based on that computer’s identifier information (clarified later)
  • Floating – a server type license installed on any computer or device that you can access from other devices on which you want NX to run.
  • Combinations of both of the above options enable the software to run on specific devices, enable only certain applications or modules of the software to run on certain devices or for certain user groups, or other managed user/device/application-based scenarios. You can even code these kinds of licenses to allow users from different departments, locations, facilities, even countries to run the software via the internet.
  • Dongle enabled – the license authorization code resides on a plug-n-play device, somewhat like a thumb or external drive. This lets NX run on any machine with the software installed, but while you have the dongle connected.

Send to Siemens

In whichever above scenario you purchase, you’ll need to provide the Siemens license administrator five things:

  1. The customer’s “Sold to ID,” available in the original, temporary license file.
  2. Adequate proof of an active maintenance contract.
  3. The host name of the computer on which NX will be used or that will used as a server to other computers that have NX installed on them. You can access the host name by pressing MB3 (right-click) on “This PC” or “My Computer” (based on operating system) and choosing “Properties.”Computer name
  4. The MAC address, sometimes called Physical address of that computer, a string of 12 characters. Often dashes separate these strings separated into pairs of characters, e.g. A4-34-87-C2-BE-9G
  5. The Composite ID (CID), a 12-character string assigned by a computer’s operating system to devices installed in a computer, generally for the purposes of communications, such as the Ethernet card, wifi card, etc.

You can access the MAC address and the CID along with the next bit of information using the NX “Licensing Tool.” This installs when NX installs. To access this icon in Windows 10, press the Windows key on the keyboard.


Licensing Tool


When selected, the MAC address and CID appear in the Composite ID group…



You’ll have more luck using the CID of the Ethernet card. Sometimes wifi is disabled, or if wifi is not available at the location, it may not be active. The Ethernet card is almost always enabled and tends to work the best.

Fixed node license files

To keep it simple, let’s review a fixed node license file intended to limit available applications (modules within the software) to specific computers (that meet the hardware certification specifications available on the GTAC website).

Once you send the above information to Siemens, they send an email to the customer containing the NX license file. Depending on the products purchased, they send other licenses for Teamcenter, etc. The file name appears as “License_Ugslmd.txt” when emailed.

Due to firewalls and other anti-malware and protective software security programs, Siemens defines the file extension as “.txt.” This way it passes through those email filters successfully. The customer should rename the file with the more common format that indicates it is a Siemens license file. For example, for the file name “splm12.lic”, “12” indicates the version of the license file and the “.lic” allows the NX software to recognize and read it. A sample of the content of the fixed node license file follows. Note the version of the license file inside the header at the top surrounded with # symbols.


Version of License File


  • The first section of the file lists the “packages” as product numbers (bundles) and specific application modules licensed by the file.
  • The “options” listing is a collection of proprietary coded strings of hexadecimal characters in groups of 4. This is an example of the customized data that is generated from the MAC address and CID of a particular computer.
  • This is then followed by individual “feature” sections. They include specific NX license server version (Parasolid), expiration date (or “permanent” if so licensed), fixed node host id references (MAC address), and options information. It also includes more hexadecimal code that enables that specific functionality.

Floating “Server” license files

A floating license file is similar to the fixed node license explained above with some minor differences in content but major differences in capability and how it is applied.

When you need more than one computer (user) with NX licensing simultaneously, you can employ a floating license server. This allows an unlimited number of users to run NX using that one license file that resides on the server. However, the number of simultaneous users is limited to the total number of licenses authorized by the license file. In other words, the license server stores the total number of licenses in a pool individual users can access at any time. If you try to request a license from the server by starting an NX application without any unused licenses, you can’t. An alert will pop up indicating that the particular module they wish to use is not available.

What’s Inside?

One of the main differences is that directly underneath the header of the file will be a “server line.” This starts with the word “SERVER”, followed by the computer host name where the license file resides, the CID of that computer, and the port number used.

  • Sometimes, Siemens will send floating license files with server lines containing “YourHostname” instead of the actual customer’s computer host name. You will need to edit this – the actual host name must replace “YourHostname”.
  • This must then be followed by the host computer’s CID. In temporary license files, that will often just say “ANY”, meaning any computer. For all other license file types, you must enter the CID. Usually, you only need to edit this and the host name.
  • Lastly, it lists the port number. It uses port number “28000” as the default. Any port number available on the computer works (but you usually want to leave it alone). Sometimes more complicated configurations use 27000.
  • You’ll find the “vendor” line in the line below the server line. This identifies which specific software product being licensed. It also reflects the actual server process that needs to be running on the computer for this license file to enable the software to run. When you make changes to the configuration, this service usually needs to be stopped, restarted, and the license file be reread.
  • After that, the same “package” section follows that lists the license bundles. Then comes sections similar to the above “features” definitions identified as “increments”.



At the bottom of either the fixed node or floating license files you can find a “Software License to Feature Name Cross Reference” listing. This summarizes the actual functionality in groups, listing the specific “license features” under the bundles that the license file enable.




The Flexera “Flexnet” software that enables NX and other Siemens PLM Software products to run seems complicated because the intricacies prevent unauthorized use. However, when properly installed and configured, it becomes virtually transparent to the user of the application. The average CAD or CAM user doesn’t need this information unless problems arise with the licensing or network. Then it helps to understand it, or at the very least, what might fail when if NX doesn’t start successfully.

I hope this article provides you with some insight into what processes when you are creating your models. Perhaps it even takes a little of the mystery out of understanding an installation of NX licensing.

Swoosh Support Services

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.