I have an E-Port dock station and Dell Latitude E7440. I have recently switched from Windows 7 to Windows 8.1. System stopped detecting external monitor connected to my dock station.
Regardles of which port I use (VGA, DVI, DP), in the screen options in Windows the second display is always visible as VMM2300 ROM. It is greyed out and cannot be turned on.
When I connect the display directly to the laptop (with HDMI or HDMI -> VGA adapter) – screen is working.
Where the problem might be? I have already installed the newest graphic drivers and visited troubleshooting page with no luck.
Best Answer
Solution was to install Synaptics VMM2320 MST HUB Firmware Update A01.
The version A05 suggested by the troubleshooting page did not work for me (I could not install it).