5a693e87_Plus__known_issues____RealVNC___Workaround
[ID] 197 [Description] Mounting an image while connected via Wi-Fi may cause the host computer's operating system to lose Wi-Fi connectivity entirely. (VNC Viewer Plus is disconnected, and cannot reconnect.) [Status] Fixed in 1.2.5. [Workaround] 
Turn the host computer off and repair Wi-Fi connectivity using operating system diagnostic tools.
VNC® Viewer Plus (known issues) - RealVNC®
Workaround