How to fix a sideways screen on Windows 7/10
To rotate your screen on Windows 10, right-click your desktop, and then select the “Display Settings” command. In Windows 7, right-click the “Screen Resolution” command instead.
On Windows 10, you’ll be taken to the Settings > System > Display window. On Windows 7, you’ll end up at Control Panel > Appearance and Personalization > Display > Display Settings.
Locate the Orientation option under Resolution, click the dropdown menu under it, and then choose your preferred screen orientation—Landscape, Portrait, Landscape (flipped), or Portrait (flipped.)
This window looks different on Windows 7, but has the same Orientation options.
If you don’t see a screen orientation option in the Settings app on Windows 10 or the Control Panel on Windows 7, try updating your computer’s graphics drivers. This option may be missing if you’re using generic video drivers that aren’t appropriate for your computer’s graphics hardware.
How to Rotate Your Screen With Hotkeys
Some PCs have hotkeys that quickly rotate the screen when pressed. These are provided by the Intel graphics drivers, and are only enabled on some PCs. If your PC’s display suddenly rotated while you were pressing something on the keyboard, you probably triggered the hotkey accidentally.
To rotate your screen with hotkeys, press Ctrl+Alt+Arrow. For example, Ctrl+Alt+Up Arrow returns your screen to its normal upright rotation, Ctrl+Alt+Right Arrow rotates your screen 90 degrees, Ctrl+Alt+Down Arrow flips it upside down (180 degrees), and Ctrl+Alt+Left Arrow rotates it 270 degrees.
You can change these hotkeys—or disable them, if you want—using the Hot Key Manager tool in the Intel Graphics Control Panel on your PC. To access it, right-click your desktop, and then select “Intel Graphics Settings” or press Ctrl+Alt+F12 to open the Intel control panel. Click Options, and then head to Support > Hot Key Manager.
If you don’t see the Intel Graphics Settings tool on your PC, you probably aren’t using Intel graphics. If you don’t see the screen rotation shortcuts on the Hot Key Manager screen, they aren’t available on your PC.
How to Disable Automatic Screen Rotation on Windows 10
Convertible PCs and tablets running Windows 10 automatically rotate their screens as the device orientation changes. This works just like modern iPhones and Android smartphones. To stop your screen from rotating automatically, you can enable Rotation Lock.
To do so, open the Action Center by clicking the notification icon at the right side of your taskbar, or by pressing Windows+A.
Click or tap the “Rotation Lock” quick action tile to lock your screen in its current orientation. Click or tap the tile again to disable Rotation Lock.
The Rotation Lock option is also available at Settings > System > Display.
If you don’t see the option in either place, then your device doesn’t support automatic screen rotation because it doesn’t have built-in accelerometer hardware.
If the Rotation Lock tile appears grayed out, you must put your convertible PC into tablet mode—for example, by rotating its screen around or by detaching its screen from the keyboard. Rotation Lock isn’t available in standard laptop mode, as the screen will never automatically rotate itself in standard laptop mode.
Do throw in your comments in the comments section to tell me how it goes or if you run into any problems along the process.