Troubleshooting the 'IAR License Server Tools'

Technical Note 99016






4/20/2023 5:57 PM


This information applies to users using the 'IAR License Server Tools' to share licenses over a network. You need to be on the server computer.


The problem that no license is supplied from the server can be due to different reasons. Possible symptoms are:

  • There is no server license at the server. See A) an B) below.
  • There is a license, but it is shown as 'invalid'. See C) below.
  • There is a valid license on the server, but clients can not get licenses. See D) below.


A) Check that 'Activation' works

During the Activation of a license server communication takes place to IAR via the Internet. This can fail.
The IAR License Manager communicates with IAR using SOAP over https (port 443).
So open that port, and try again to activate the license.

B) Check for the file 'lservrc'

The license is stored in a file named lservrc. If the location for this file is protected, then the IAR License Server Tools cannot hand out licenses. Check the write privileges for the directory of

C:\Program Files (x86)\Common Files\SafeNet Sentinel\Sentinel RMS License Manager\WinNT 

Try again to activate the license.

C) License is 'invalid'

The dongle driver might not be installed as it should be. Go to Technical Note 44489. Test the suggestions there.

D) Check network

The clients broadcasts for the IAR License Server Tools on UDP port 5093. This port must be open in the server, or it won't be found by the clients.
Open the port on the server, and on any intervening network 'bridges'.
Try again from the client.

Update the server application.

Check if there are new versions of IAR License Server Tools, and if yes, then install them and see if that solves the problem.

Applies to

This Technical Note applies to IAR System products that uses License Management System version 2 (LMS2).


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