Run a port scan to ensure no other application or service is using the port you have configured into the QLALicense.dat file. If you have determined that no other service is using that port, stop the QLA Service and then try launching the QLA Server as an application. If another application is using that port number, configure a different port number on which the QLA Server may listen.
Alternatively, you can reinitialize the QLA Server after you delete the HWMusage.dat and Save.dat files that are located in the Server folder of the Quark License Administrator folder.
This error most commonly occurs when you have launched the QLA Server as an application when QLA is already running as a Service. It is also possible that the port designated in the QLALicense.dat is in use by another application or service.