Authenticating Premier Pro CS6 on a CD

Hello - I purchased (legally) a copy of Premier Pro CS6 in 2013 - it came on a CD.  I have been using it for many years. My computer crashed the other week and I lost the program.  I have had a new drive fitted to the computer and now I want to re-install my copy of CS6.  When I run the CD I'm told I must authenticate the software - but the website I'm given no longer works.  The computer on which I run CS6 is offline, so I need to authenticate it from a separate computer.  I'm at the end of my editing career so I don't want to get into subscribing for the most up to date versions - I just need to do a few odd things using my existing software.

Can anyone advise on how I can authenticate it?

Thanks.

John

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