By the looks of things, you have exceeded your 2 activation limit. An individual license allows you to install your app on up to 2 devices concurrently. If you wish to install a 3rd time, you MUST DEACTIVATE one of the previously installed versions from the Help Menu. See below for more details.
https://helpx.adobe.com/download-install/kb/activation-deactivation-help.html
Due to CS6's advanced age, a reset of your activation count is no longer possible. The legacy CS apps are 12+ years old.
MODERN OPTIONS: =============== FREE Acrobat Reader -- view, comment, print & sign PDF. https://acrobat.adobe.com/acrobat/pdf-reader.html Paid Acrobat Pro -- the complete solution for creating and saving PDF. https://acrobat.adobe.com/acrobat/acrobat-pro.html Photoshop Elements or Premiere Elements (no subscription needed). https://www.adobe.com/products/photoshop-elements.html Creative Cloud Photography Plan ($10/month for 12 months). Includes the following:
Photoshop CC and Photoshop on iPad
Camera Raw
Lightroom on desktop, mobile and the web
Lightroom Classic
Portfolio website + hosting
Adobe Express (free starter plan)
Bridge
20 GB cloud storage (upgradable to 1 TB).
Free upgrades for paid subscribers
https://www.adobe.com/creativecloud/photography.html Creative Cloud bundles and Single App Plans for mobile, web & desktop https://www.adobe.com/creativecloud/plans.html
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