Uniface supports the use of OAUTH2 for authorization of external apps such as MS Outlook and Gmail
and enables you to use UPOPMAIL to access your external mailbox.

Rocket Uniface Library 10.3 > Uniface 10: Changes per Release > What's New in Uniface 10.3.03 > Uniface 10.3.03: Consolidated Doc Updates for New Features
Rocket Uniface Library 10.4 > Uniface 10: Changes per Release > What's New in Uniface 10.4.01 > Uniface 10.4.01: New Features Since 10.3.02
contain in Other Features:
UPOPMAIL component supports OAUTH 2.0 standard through the use of new security drivers for POP and SMTP

In this sample we will explain what OAUTH2 is and which steps are involved to enable your UPOPMAIL application to use OAUTH to access MS Outlook or Gmail accounts.
Although this blog will limit MS Outlook and Gmail, the mechanism can be used or all types of mailboxes that require OAUTH2.