Most mouse scroll wheels work right out of the box. Usually, the wheel works even if you don't install the mouse's software, but if you can't get a new mouse to scroll, try installing the software as a first step. If that doesn't work, or if your wheel used to scroll but stopped working, the problem could be a hardware, software or setting issue.
Check the Basics
Before trying anything more complicated, start with these basic troubleshooting techniques:
- Reboot your computer.
- Clean debris from the wheel. If necessary, unplug the mouse and use a drop of Isopropyl alcohol on a cotton swab.
- Connect the mouse to a different USB port on your computer, if possible.
- Replace the mouse's batteries, if you're using a wireless mouse. Old batteries can cause erratic behavior before they totally die.
- Try scrolling in a different program. Microsoft notes that some programs have issues with scroll wheels, so test the wheel in a program such as Notepad or Word.
Check System Settings
In Windows, the Mouse Control Panel houses various mouse settings. Mouse drivers -- the software included with a mouse -- can change the settings in the Control Panel, so the settings might look different from computer to computer.
To reach the Mouse Control Panel, open the Start screen in Windows 8.1 (or Start menu on Windows 7), type Mouse and select Mouse from the search results.
In the Control Panel, open the Wheel tab and check the settings for any options that might be causing your problem. For example, the default Wheel tab settings offer different speeds for scrolling. If your wheel scrolls slowly, turn up the speed.
Some mice, including some of Microsoft's mice, have the option to completely disable scrolling. If your wheel won't scroll at all, make sure scrolling is enabled. Not all computers offer this option.
Check for Driver Updates
Updates to mouse drivers can fix glitches, including scroll wheel issues. Windows Update can update many drivers, but won't do so automatically, even if you have automatic updates turned on. To check for driver updates, search for and run Windows Update on the Start screen (or Start menu) and click Check for Updates. When Windows Update finishes searching, click the link to see Optional Updates.
If you see your mouse in the list of optional updates, check it and click Install. If your mouse doesn't show up in the list, you might have current drivers, or Windows Update might not offer your mouse's drivers. Instead, visit your mouse manufacturer's website (such as Microsoft, Logitech or Razer) to download the drivers yourself. Even if you have the latest copy installed, there's no harm in downloading it and installing it again -- it might even clear up your problem.
Remove Old Mouse Software
Having software from two different mice installed at the same time might cause conflicts, leading to erroneous settings in the Control Panel and problems with the wheel. Check the Programs and Features Control Panel -- search for it on the Start screen or Start menu -- for mouse software from mice you no longer use. Select any you find and click Uninstall. Afterwards, if the problem isn't resolved, try reinstalling the software for your current mouse from its CD or the manufacturer's website.
If nothing works to solve the problem, your scroll wheel might have simply broken. In this case, you'll need to have the mouse repaired or buy a replacement. Check whether the mouse is still in warranty from the manufacturer to potentially repair it for free.