Adobe Reader non DC version

Due to security requirements in our organization the access to internet is limited (especially for storing files in cloud).

We have many complaints from users regarding that the Reader is taking a long time to open, not responding etc.

I have been checking log files on firewall, it all the time tries to connect to cloud.acrobat.com, although the user is not signed in the adobe cloud.

I have went through preferences and set off anything which might be the reason to go to the internet (anonymous statistics, comment checks, etc.)

How can I limit that adobe reader does not try to connect to the internet?

If it's not possible, then we will have to choose other vendor product...