Let's see if you use the same cable. VGA has this sense pin 10 that can cause this. Either the cable fails or other. I mention as a possible but worth checking with their cable.
Try manually setting the resolution and refresh rate.
Hello,
the connection worked fine in the past, however since recently when I connect my lenovo laptop with Windows 7 using VGA to various projectors, it shows no signal on the big screen. The same lenovo model of my colleague works fine. My laptop recognizes that a projector is connected since the resolution of the screen is changing to the resolution of the projector and you can see the connection in the display settings! I tried to switch between various projector setting (duplicate, show only projector etc). I also updated my driver for the graphics car (Nvidia GeForce 410m)! Nothing works! Please help!

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