Hello Rebecca,
Welcome to Microsoft Community.
This issue might occur when any program is being installed or updating in the background. You may try the following and check if it helps.
Step 1: Clean Boot
A clean boot is performed to start Windows by using a minimal set of drivers and startup programs. This helps eliminate software conflicts that occur when you install a program or an update or when you run a program in Windows. To know more, follow the article below:
http://support.microsoft.com/kb/929135
Note: After troubleshooting, refer to this section ‘How to reset the computer to start normally after clean boot troubleshooting’.
Step 2: Run the System Maintenance troubleshooter
Run System Maintenance troubleshooter to diagnose the exact issue. This troubleshooter will detect and resolve the basic issues or settings which might cause this issue.
Follow the steps mentioned below.
a. Press “Windows key + W”.
b. Type “Troubleshooter” without quotes in the Search box and hit enter.
c. Select “System and Security”.
d. Select “System Maintenance” under System options.
e. Follow the on-screen instructions to run the troubleshooter.
If the issue persists, try to restart the "Windows Installer service", to do so, follow the steps below:
- Press Windows + R on the desktop screen.
- Type services.msc and hit enter.
- Scroll down to the "Windows Installer" service and double click on it.
- Click on Restart service to restart the service.
Hope this information was helpful.