I had so much trouble with it.
 
 

Solution

Go to %APPDATA%\Red Alert 3\Profiles\<user-id>\
 
Open options.ini.
 
Change Resolution xxx xxx to your desired resolution.
 
 
 

Other method

1. Make a desktop shortcut
 
2. Enter the shortcut properties
 
3. In the first row, after game`s path, type: -xres 1920 -yres 1080
 
4. If there are still some problems try -win -xres 1920 -yres 1080
 
There must be space between the commands and the object path
 
 

 
 
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