IAR Embedded Workbench running on a Client PC does not get a license from the License Server application running on the Server PC.
The client-server communication is handled via the UDP protocol, port 5093 on the network. If a firewall or network bridge is installed between the client and the server, the minimum requirement (Network Requirements.pdf) is that UDP packets at port 5093 are routed.
See too that UDP port 5093 is opened. See hints in Technical Note 29096.
If the above suggestion does not help, then please read on. For example, this can happen if the Client PC has several network interfaces.
The Windows Firewall can be set up with rules for specific executables. Set up one rule (on the Client PC) for each of the...
IarIdePm.exe and LicenseManager.exe (found in your IAR Embedded Workbench installation directory in common\bin )
licman.exe ( C:\Program Files\Common Files\IAR Systems\License\Utilities )
...applications. The firewall rule should allow each of the applications to communicate on all UDP ports.
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