Weird mouse wheel behavior in Outlook and Word (Microsoft 365)

1. Check mouse driver/settings
Update mouse driver (for external mouse)
Open Device Manager (Win + X > Device Manager)
Expand “Mouse and other pointer devices”
Right click on the mouse device > “Update Driver”
Select “Automatically search for drivers”
Adjust scroll wheel settings
Open Mouse Settings (Win + I > Devices > Mouse)
Adjust “Lines per scroll” (recommended setting is 3-5)
Turn off “Smooth scrolling” (supported by some mouse drivers)
2. Fix Office Applications
 To quickly fix Office
Open Control Panel > Programs and Features
Find Microsoft 365 > Click “Change”.
Select “Quick Fix” > “Repair”
Restart your computer when done
Reset Office settings
Close all Office applications
Press Win + R, type the following command and enter:
cmd
outlook.exe /resetnavpane
Reopen Outlook/Word to test
3. Check for Windows and Office updates
 To update Windows
Win + I > Windows Update > Check for updates
Install all optional updates
Update Microsoft 365
Open Word or Outlook
Click File > Account > Update Options > Update Now
4. Disable potentially conflicting add-ins
Open Word or Outlook
File > Options > Add-ins
Select “COM Add-ins” in the bottom management > “Go To”
Uncheck all add-ins > Click “OK”
Restart the application to test
5. Ultimate Solution
If the problem persists:
 Uninstall and reinstall Microsoft 365
Use the official uninstall tool (download link)
Reinstall from office.com
Test with a different mouse
Try using a different mouse to confirm if there is a hardware issue