Windows defender error 0x800700AA, service can not be started comes when the user is trying to run Windows defender scan on their system.
This kind of behavior happens for two reasons mostly, third-party application conflict or corrupted system files.
In this article, we will tackle both scenarios and provide you with solutions in both cases.
In this rare scenario when Windows defender can not start scan due to conflict with installed service or application in the system solution is quite simple. Restart your PC into safe mode and run the scan from there. In a safe mode environment, minimum drivers and services are only loaded eliminating any conflicts that might occur when everything is booted. If Windows defender can not run the scan in safe mode and you get the same 0x800700AA error then you can eliminate application conflict as a reason and move to the next solution which will tackle corrupted system files. If you, however, managed to run a scan then you have a rare third-party application conflict, you can boot normally into windows and try to eliminate one by one to see which one is causing the issue. The safest bet would be to start with security software because most of the time that is what causes conflicts in running services and applications.
If the previous solution has not provided you with results then you have system file corruption that needs to be fixed. Move from one solution to another as presented below:
SFC scan is a built-in Windows tool for solving corrupted system files issues, it is fully automated and does not require from the user any kind of knowledge or information. To run it and scan the system do the following:
Press ⊞ WINDOWS + X to open the secret menu
Left-click on the command prompt (admin)
In command prompt type SFC /SCANNOW and press ENTER
Wait for the process to finish, do not interrupt it and once it is done, restart your computer
DISM scan is similar to SFC scan but it tackles different types of system file corruption and it is recommended to run it also after SFC has been completed. Please note that for DISM scan to be successful you will need a stable internet connection since DISM will replace corrupted files with new ones downloaded from Microsoft. To run it do the following:
Press ⊞ WINDOWS + X to open the secret menu
Left-click on the command prompt (admin)
inside command prompt type: exe /online /cleanup-image /scanhealth followed by ENTER, then type: Dism.exe /online /cleanup-image /restorehealth also followed with ENTER.
Leave scan to finish and reboot your PC

Error CausesError codes on Windows devices can result from many reasons, including lack of proper PC maintenance, the presence of malware, and issues related to servers. In the case of error code 0xc00007b, it manifests itself on various versions of the Windows operating system when users attempting to run applications incompatible with their system or use the incorrect bit location. To correct these issues that may be causing error code 0xc00007b, users will need to use manual repair methods listed in this article. Failure to rectify this error code could result in others such as error code 0xc0000142.
The manual repair procedures listed in this article do not require extensive technical knowledge. Thus, even average Windows users will be able to apply these solutions in order to fix error code 0xc00007b in Windows 8. However, in case of difficulty applying the solutions listed below, contact a Windows repair technician.
One of the first manual repair methods you can attempt is to use Windows Update. This will enable users to access the latest updates for the version of Windows they have on their system. To update your system, follow the instructions below.
After you’ve completed the installation of the latest updates, reboot your machine then attempt to run the gaming application you were unable to open due to error code 0xc00007b. You should be able to run the application if Windows Update fixed the issue. However, if the error code reoccurs, proceed to the next manual repair method by installing Microsoft DirectX.
Another important manual repair method relates to the use of DirectX, a free tool available to Windows users regardless of the version of the Windows operating system present on their PC. Visit Microsoft’s official website and search for DirectX End-User Runtime Web Installer. Ensure you access the latest version of the program, then click download.
The app enables Windows users to access high-speed gaming by providing a powerful platform for games and multimedia applications. Access to the latest version of DirectX can help users fix the issues causing error code 0xc00007b in Windows 8.
When the installation process is complete, reboot your PC, then proceed by checking if you are able to run your gaming applications. If you are still unable to run the applications the issue will need to be resolved via another manual repair method.Access the latest version of Microsoft’s .NET Framework to complete the final manual repair method. Be sure to follow the steps listed below to download the latest version of the .NET framework. This is crucial as only the latest version of the framework is equipped with the necessary capabilities required to successfully address the issues causing error code 0xc00007b on your device.
Restart your computer after you’ve downloaded the latest version of the .NET framework. Open the gaming application you were previously unable to run due to error code 0xc00007b.
You’ll be able to access all your gaming or multimedia programs if the issue was resolved via this manual repair method. Otherwise, you may need to reinstall the programs you are unable to run as there may be an issue with the program itself resulting in software conflict or the inability to run other gaming programs.
If you wish to always have at your disposal a utility tool to fix these Windows 8 and other related issues when they do arise, download and install a powerful automated tool.
"Error Code 0x80070057: The parameter is wrong"When this problem happens, you will end up struggling to move private documents from one person to another.
Error Causes"An Internal Error has occurred. Incorrect parameters".If this happens to you, realize that you are dealing with malfunction code 0x80070057. This error occurs mostly when you are trying to build a full backup of your Windows 7 OS.
A few days ago we celebrated fixing of months-long PrintNightmare vulnerability by Microsoft, sadly a new bug and issue have been found.
Firstly discovered Microsoft stated:
A remote code execution vulnerability exists when the Windows Print Spooler service improperly performs privileged file operations. An attacker who successfully exploited this vulnerability could run arbitrary code with SYSTEM privileges. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.A few days ago, Microsoft officially released a patch that was supposed to finally fix it. As you might recall this vulnerability was present for quite some time, Microsoft's solution after a long struggle was to elevate certain privileges to administrator account only and remove user accounts from managing printers. It complicated things a little bit but it was stated payoff was worth it. The new issue now is that on a system that already had accounts created and set, old accounts still can hijack the system, patch issues address only accounts that are created after the fix is administrated, old ones can still do whatever they want. Once again of course Microsoft has stated that until it is again resolved you should again disable the Print Spooler service as a temporary workaround.
When Windows 11 update is available but you do not wish to restart right away because you are in the middle of using a computer, you can schedule a restart for up to 7 days. It is very easy and we will show you how to do it.
Error Causes