In addition to the above response.
1- PDF Pack is an online service that you can use online via: https://cloud.acrobat.com/exportpdf
2- You can also use the services through free desktop version of Adobe Acrobat Reader DC: Adobe Acrobat Reader DC Install for all versions
3- “Sign In” using the email (Adobe ID) under which you have subscription registered.
4- For detailed description of how to use the PDF Pack service, you may refer to- How to Use Adobe PDF Pack
You may refer to the following link for any troubleshooting: Troubleshooting Create PDF, Export PDF, Adobe Send, Fill & Sign … services(PDFPack or Document Cloud...
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