(PC) - How to disable the Blue Line on screen (VCA Line)

VCA Rule Line can help you easily find out the VCA area.   You may turn it off from here.

Stop the View first.  Go to the Gear icon.

Go to Image tab > switch VCA Rule to Off

Then, try to play the video again.   

For some DVR/NVR LiveView local monitor display blue/green line issue. 
Use this way that should solve the issue.

Or, you can go here to find the setting from here.