Windows 10: Changing resolution in second monitor

I'm running Windows 10 on a Dell XPS15 laptop. I have hooked up a second monitor, and I get the "Input Not Supported" message on the second monitor an older Acer monitor. I believe I can get rid of it by changing the resolution on the second monitor, but I can't figure out how to do so. Help? Thank you.

:)

 

Second monitor screen resolution problem

Hi,

For us to properly isolate the issue with your second monitor screen resolution, we would like to know the following:

• 
  Were there any changes made on your computer prior to the issue (e.g., updates, software installation)?
  
• 
  When did the issue first begin?
  
• 
  To make sure that we have not missed on anything, what troubleshooting steps have you done so far?
  

In the meantime, we suggest that you try resetting your monitor settings, and check if the issue still persists. You may refer to your monitor on how to reset it.

We look forward to your response.

 

second monitor resolution

Everything worked great until I moved my computer. Now, I can not change the resolution on my second monitor. I am using

Windows 10. The resolution bar, only on monitor #2, is greyed out. I tried switching the monitors but either one is stilled greyed out when used as #2. Monitor #1's resolution can be changed , no problem.

 

Resolution of second monitor messed up after resolution change

I changed the resolution of my second monitor (Emmrson 19" TV, my first monitor is a BenQ 27") and now it no longer fits on the screen, even if I put it back to the resolution it was in before. I have tried to change the scaling on it but that didn't work.

Also, as soon as I unplug the first monitor the original resolution works again.