Hi George,
You probably upgraded from Vizard 2.17 to Vizard 2.5x. The licensing model has changed for this upgrade, but the new license will be issued to you free of charge to existing customers.
Please start Vizard and click 'register license' and send the harware code to
contact@worldviz.com, and we will immediately send you the new license code.
All best,
The WorldViz team