Hi I have ASUS tablet with Windows 7. I use USB to VGA converter to connect to VGA projector. It used to work until June 4 at 5:30PM PST, when it stopped working during presentation. Before that it worked for 4 months. Looking at control panel adjusting external display if I select duplicate to projector I only get my computer display. It says it does not detect external display.
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Sounds like it is still under warranty. you should contact the manufacturer.