There are a few extra buttons on the ViewClix remote control that are reserved for future features in the ViewClix Slideshow:  the Menu button (3 horizontal lines) and the Asterisk button.

That being said, during the start-up of the ViewClix frame, the three lines Menu button can be used during start up to "Forget all WiFi networks" https://help.viewclix.com/portal/en/kb/articles/forget-previous-wifi-connection

Also, the Asterisk button can be used to display the the frame's Mac Address during start up: https://help.viewclix.com/portal/en/kb/articles/display-wifi-mac-address