Error: This computer must be connected to the network in order to open this document.

Hello Fabios,

Sorry for the delayed response and inconvenience caused. Is this PDF file has security settings that only work with a particular network address?

Check the settings under Edit -> Preference -> Security -> Security Setting -> Server Setting tab you can find the setting.

Try connecting the machine to a different network environment like a guest wired/wireless network or a mobile hotspot and see if you still get the error message.

Is it specific to one PDF or all PDFs are throwing this error message?

Have you tried with other PDF files?

Are you trying to open the PDFs that are stored online? Are you able to open PDF files that are stored locally on your computer?

It might be a proxy server or a VPN rights related issue.

Check for the latest updates of Adobe Reader from help>check for updates, install the updates and reboot the machine and see if this brings any difference.

If the issue persists, please use Acrobat cleaner tool to remove Adobe Reader Download Adobe Reader and Acrobat Cleaner Tool - Adobe Labs Reboot the machine and install Adobe Reader from Adobe - Adobe Acrobat Reader DC Distribution

Let us know how it goes and share your findings.

Regards,

Anand Sri.