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1. Uninstall Photoshop CC <version number> using the uninstaller.
2. After the Photoshop uninstall completes, make sure that the following folders have been deleted:

• Windows
  • C:\Program Files\Adobe\Adobe Photoshop CC <version number>\
  • C:\Program Files\Adobe\Adobe Photoshop CC <version number>\Required\CEP\extensions\
  • C:\Program Files\Common Files\Adobe\Plug-Ins\CC\Generator\
• Mac OS
  • MacHD/Applications/Adobe Photoshop CC <version number>/
  • MacHD/Library/Application Support/Adobe/CEP/extensions/
  • MacHD/Library/Application Support/Adobe/Plug-ins/CC/Generator/

If these folders or any subfolders are still present, manually delete them.

3. Reinstall Photoshop CC <version number> using the Creative Cloud desktop application.