Search Support Database

Valid License Could Not Be Found in Noxturnal

This article is relevant to all Noxturnal users that experience issues with a valid license being found on their computer.

The error message as depicted here below where the Noxturnal software is being opened. This error indicates that the license file (license.lcx) cannot be found by Noxturnal.


Root Cause of Issue

There is a Windows Group Policy setting that triggers this error message and Noxturnal cannot be opened. This setting has to do with the FIPS compliant algorithms for encryption.

The Federal Information Processing Standard (FIPS) Publication 140-2, (FIPS PUB 140-2), is a U.S. government computer security standard used to approve cryptographic modules. This computer security standard is pushed to computers using Windows Group Policy.

The image below shows how this group policy is set. In the Local Group Policy editor under Windows Settings > Security Settings > Local Policies > Security Options the group policy System cryptography: Use FIPS compliant algorithms for encryption, hashing, and signing is set to Enabled.

If this policy is enabled, the Noxturnal license file cannot be read and Noxturnal software cannot be opened.



To solve this issue navigate to Program Files > Nox Medical > Noxturnal and locate a config file named noxturnal.exe.config


Replace this config file with the config file that is included in this article as an attachment. Note that you need to have administrator privileges to be able to replace this file. If you are not able to download the file, please contact 

Please note that if you can‘t see the config file, you may have your system configured to hide system files. If this is the case, please ask your Administrator to locate this file for you

Once this config file has been replaced with the new config file please test if you can open up Noxturnal.


*Please note that not all features or all products are available in all markets. Our products are medical devices and subject to registration/approval in each market area. For more information on product availability please contact

Print Friendly and PDF
Was this article helpful?
0 out of 0 found this helpful

Have more questions? Submit a request