Usually, such is a setting in the driver or some utility program or hidden under a function key. That should be in the user manual.
Maybe also, you need to upgrade the driver to be fully compatible with Windows 10.
If you can't find out, Acer customer service or the shop where you bought it might know. I like shops with a great after sales support.
Also, remember you have 30 days to go back to Windows 7. So better take action now.
Kees
I have an Acer Z5600 all in one, I use to have an additional acer A1916W monitor connected using win 7 since I upgraded to Win 10 when I connect the other monitor my pc just goes to a black screen does anyone know why

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