This is still the same behaviour in 2022 on Windows. When a user no longer has Acrobat Pro/Standard licence, Acrobat Pro/Standard shows a 'buy license now' or 'sign in' prompt. Closing either prompt would exit the Acrobat program with no further explanation.

Creative Cloud Desktop App can also aggravate the issue. For example, on a machine pre-installed with Adobe Reader DC only, and a user with an Acrobat Pro/Standard license logs in to the CC Desktop App, the CC App would auto-upgrade Reader DC to Pro/Standard DC, but the other way is not true. It would not downgrade to Reader when a user signs out or loses license.

The auto-upgrade feature would be beneficial if, Acrobat behaves in a read-only mode with no active license. Also, auto-upgrade is not consistent, so sometimes, users with an Acrobat license would be stuck on Reader DC, while the CC Desktop app reports the Acrobat DC is installed and up-to-date. If Acrobat DC can behave as read-only mode, then we don't have to bother installing Reader DC and Acrobat DC side-by-side and deal with switching Default Apps between the two.

Commenting for visibility.

In the era of work-from-home we now have all of our users logging into a multi user terminal server.

When our non-licensed users try to open the new 64-bit unified Adobe Acrobat/Reader they get a sign-in prompt. When they click the X because they don't have an account Acrobat closes.

Instead of closing it should switch to Reader mode.

This should not be the case if you purchased the program. Adobe needs to be held accountable for false purchases and not having programming that installs properly.

It does not work in Reader mode after the trial period is expired.

Hi Saad,
This indeed is the design, after the trial expires Acrobat works in reduced mode which is equivalent to using a Reader, can you elaborate on what Reader feature you miss out after your trial expires?

Thanks