My motherboard has 1 DVI port and 1 HDMI port. I recently purchased another monitor and so I have one monitor gong HDMI - HDMI and that works fine,and for my other monitor I am using a VGA cord with a DVI adapter on the computer end. The VGA - DVI monitor always comes up with a no HDMI signal error. How do I fix this?
Are you sure that DVI port isn't digital only? Not all DVI ports support analog and digital. You should use a DVI to HDMI cord for the other monitor. Since it appears to support HDMI. A digital connection is the preferred connection anyways. It provides a cleaner signal.
Have you tried changing inputs on the monitor? Also go to Display in Settings > System and see if both monitors are listed (Windows 10, older versions of Windows use the Control Panel). If so make sure under "Multiple Displays" the one not in use is set to "Extend desktop to this display" not "Disconnect this display".