I generate on SolarWinds Support website my NTA license. I don't use it directly because i re install NTA. Now, i want to use the license et system tell me that this license is for another computer/software package.
How can i do to reset this license that i never use?
Your issue is probably that the Product Serial Number has changed after re-installing NTA.
You will have to open a support ticket and select "customer service" for the "SolarWinds application" field.
Specify the name of the computer for which you generated the license as well as the product and you should receive an email later telling you the license has been reset.
To Open a Ticket: http://www.solarwinds.com/support/ticket