how to get authorization number for ArcGIS
You have to register it after downloading and installing... did you complete that?
It depends on the software package. Can you be more specific on the software you are using? Desktop? Pro? Server? ArcGIS Online?
If Desktop, is it a student version, a home use version, or something thru work? If the last one, check with your license manager/administrator. If that person is you, check on the MyEsri page, your customer service rep, or local distributor.
As you can see, your question has too many possibilities answers.
If you are looking for a trial license, you could sign-up for the ArcGIS trial http://www.arcgis.com/features/free-trial.html . Once you activate your account, you will receive a mail from Esri containing an EVA********* code (12 characters). Follow the steps as suggested in the mail.
If you have recently procured an Esri license from a distributor, you will need to contact the distributor for the authorization code.
I have already signed up but before entering it to activate the software, I lost it.
contact tech support
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