@CONSOLE Alfredo, Thanks for posting in Q&A.
Based on the information you provided, it seems that you have configure the SYSTEM SECURITY - UNLOCK MOBILE DEVICES setting under Android device compliance.
1.When should this rule be triggered? Only the entered password meets the settings you configured will trigger this policy.
2.What is it for? It is a compliance policy that identify whether a device meet the settings you configured and for this setting, it will enforce you to enter the correct password to unlock mobile devices.
3.What is the difference with the screen lock? This is not much different from screen lock; both require you to enter the correct password to unlock the device
4.Does it work on all android phones of all versions? Since it will not receive compliance or configuration policies until it’s enrolled, only Run Android OS version 8.0 and later device can enroll in Intune and will support Android compliance policy and this setting.
Hope above information can help you.
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