How to Troubleshoot Windows Defender
Windows Defender is a free program provided by Microsoft. The program is used to protect personal computers from common computer problems, such as spyware, and it also provides a firewall for users. Occasionally, you may encounter an error message when trying to use your Windows Defender program, or it may not load at all. You can take several steps to troubleshoot the problem and get your computer protected once again.
Other People Are Reading
Instructions
-
Windows Defender Won't Open
-
1
Uninstall Windows Defender. Open your Control Panel and select "Add/Remove Programs," then pick "Windows Defender" from the list. Click "Uninstall."
-
2
Reinstall Windows Defender from a fresh file. Download the program from Microsoft's site, then open and install it. Open the program after installation is finished.
-
-
3
Make sure that you don't have another firewall running that has blocked Windows Defender. If you have another firewall program installed, check the settings and make sure it is switched off, then try opening Windows Defender again.
Windows Defender Won't Update (XP and Older)
-
4
Check your Internet connection. You may not be connected to the Internet when you are trying to update. If this is the case, turn your Internet connection on and try updating Windows Defender again.
-
5
Make sure that your settings are set to update from Windows Update rather than Microsoft Update. Click "Start," "All Programs," then select "Windows Update" to check. If Microsoft Update opens instead, click on "Change Settings" on the left side of the window, then uncheck the "Use Microsoft Update" option.
-
6
Download updates directly from Microsoft's website. Downloading from the website may work better because it is the direct source. After the download is complete, open the file and let it install itself.
Windows Defender Won't Update (Vista and 7)
-
7
Check your Internet connection. If you are not connected currently, you will need to reconnect to the Internet to get the update. Reset your modem and make sure your router and Wi-Fi are on, if you use them. If your Internet still won't connect, contact your Internet service provider.
-
8
Set your computer to receive updates from Windows Update rather than Microsoft Update. Click on "Start," then open your "All Programs" menu. Select "Windows Update" from the list and navigate to the "Change Settings" option. Once there, uncheck "Automatic Updates," "Recommended Updates" and "Use Microsoft Update Service." Restart your computer and run Windows Defender again.
-
9
Download an update program from Microsoft's website. This program will force Windows Defender to update. Install the program, then open Windows Defender to allow it to update.
Windows Defender Is Too Slow
-
10
Empty your temporary Internet files and cookies. To do this, find your System Tools folder in your All Programs list. It is typically located in the Accessories folder. Within the System Tools folder, select "Disk Cleanup" to remove these files. When the Disk Cleanup window opens, select the files you would like to delete, then click "OK."
-
11
Update the Windows Defender definition pack. Open Windows Defender, then click the "Update" link to get the most up-to-date malware definitions.
-
12
Allow Windows Defender to run with minimal other programs running. Having too many programs going at once can overload your computer system and therefore slow the scanning process down. Keep the number of programs running during a scan down to only the essentials.
Windows Defender Won't Uninstall
-
13
Download and run Microsoft Installer CleanUp Utility (see Resources). This download will fix a corrupted .dll file that is preventing Windows Defender from uninstalling. After running the program, Windows Defender should be able to be uninstalled.
-
14
Use Run to uninstall Windows Defender directly if the .dll fix doesn't work. Click your "Start" menu, then click "Run." In the Run window, type "msiexec /uninstall windowsdefender.msi /quiet /log uninstall.log" and click "OK." This will uninstall the program, but only for users running Windows XP.
-
15
Use a third-party uninstallation program, such as Revo Uninstaller (see Resources), to try to force an uninstallation for users not running XP. Download the program, then install it and select Windows Defender from the list of programs that can be uninstalled. Allow the program to remove Windows Defender. You may have to restart your computer for it to uninstall completely.
-
1
