Why secure folder not working in my samsung c9 pro

[AC Question]

When i try to use secure folder then a message shown on screen that "secure folder can't set up beacuse unauthorized software was installed on the device !
Can anyone help me with this problem ?

 

[Rukbat]

You installed something (rooted the phone? a different ROM? an app?) that messes something up. If you didn't root the phone or flash a different ROM, restart in Safe Mode and see if it works then.

 

[Waleed Khokhar1]

Secure folder not working in my c9 pro. The notification appears on the screen that unauthorized software installed