Hi Gwendolyn,
The option to activate a window by hovering it with the mouse may not be enabled, and this could be a possible cause why you are experiencing an issue with using the hover function of your mouse.
Follow these steps to enable the Activate a window by hovering it with the mouse option:
- Using Cortana, type ease of access.
- On the search results, click on Ease of Access Center.
- Choose Make the mouse easier to use.
- Under Make it easier to manage windows, tick on the checkbox beside Activate a window by hovering it with the mouse.
- Click Apply and then click OK.
- Restart your computer.
Let us know if further assistance is needed.