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

California's Department of Fair Employment & Housing has widened its anti-discrimination lawsuit against Activision Blizzard and claims the publisher has been shredding vital documents relevant to the ongoing investigation.
A recent report from Kotaku described the department as offering poorly paid, highly insecure positions, with a culture of hostility towards LGBTQ+ testers. The DFEH's rewording of "employees" to "workers" now hopes to take these contractors' experiences into account.
"As a contract employee, I feel there's a lot of pressure to excel, impress, and move through the ranks as fast as you can before your contract ends and you're forced to go 3 months without income or find another job," Axios reports one worker saying. "I take pride in what I do, but it feels like it's never enough."
Activision's contentious hiring of union-busting third-party law firm WilmerHale "directly interferes" with its own investigation, it says. By going to WilmerHale, Activision appears to be claiming that all work related to the investigation is privileged and can't be shared with DFEH.
The suit also claims that Activision HR shredded documents related to "investigations and complaints", against its legal obligation to retain them during the investigation. The relevant parts of the updated lawsuit were shared by Axios reporters Stephen Totilo and Megan Farokhmanesh, the former also noting that the DFEH "fixed their misspelling of Bill Cosby's name".
"DFEH is also informed and aware that documents and records have not been maintained as required by law or by the DFEH's Document Retention Notice," the complaint reads, "including but not limited to documents related to investigations and complaints were shredded by human resource personnel and emails are deleted thirty days after an employees separation."
Reddit is one of the most popular websites in the world and how Microsoft is opening doors to everyone in its new store Reddit took a logical step and made a Progressive web application and placed it in it.
Being a Progressive web app makes it more familiar and feels like a home experience using it for a lot of Reddit users.
Reddit itself has a large community and active topics discussions all the time about anything. Bringing it to Windows as an application is, in my opinion, a great move since as an application it is independent, more light-weighted, and offering some other advantages specifically tied to being a standalone windows application.
Everyone familiar with and using the Reddit website will feel right at home in this app and you can start using it right away. “The instruction at 0xf77041d24 referenced memory at 0×00000000. The memory could not be read.”
Error CausesHoliday Photo Edit is a Browser Extension for Google Chrome developed by Mindspark Inc. and offers users a basic photo editing tool alongside links to some popular editing websites.
When installed this extension changes your default search engine to MyWay and hijacks your New Tab page, changing it to HolidayPhotoEdit. It monitors user browsing activity recording visited websites and clicked links in order to learn more about the user, this data is later used/sold to better target Injected Ads.
While browsing the internet with the HolidayPhotoEdit extension enabled, users will experience more ads throughout their search results, additional sponsored links to partner products, and sometimes even pop-up ads with special giveaways designed to lure users to buy something.
Popular anti-virus scanners have marked HolidayPhotoEdit as a Browser Hijacker, and it is recommended to remove it from your computer.