Green screen preview error?

[alfaclvi]

saying wrong encryption key on the setting page

If this happening on NVR GUI Event Configuration settings page that's something very strange.
Did you create any user other than Admin in System Configuration and logged in with that user credentials or are you restoring settings from a previously exported Config File that included an second user?
Does this (the wrong encryption) happen on HikConnect app Live View too?

 

[Vauxfan]

 

[alfaclvi]

In WEB NVR Configuration go to Local-Live View Parameters and in Encryption Key box write down the same one key you used in Network-Advanced Settings-Platform Access and apply Save

There are many howto YouTube videos about Invalid Encryption Key and Encryption Key Error