Error on Startup



Windows Defender no longer works on my computer. I have Windows Vista 64bit,
just in case that help any. Whenever I try to manually load (or even when my
pc tries to load it automatically) I get the following message:

"Application failed to initialize: 0x800106ba. A problem caused this
program's service to stop. To start this service, restart your computer or
search Help and Support for how to start a service manually."

I have tried everything, even re-installation but it will not let me. If
anyone could help it would be greatly appreciated.

Bill Sanderson

The most frequent cause of this error is third-party antivirus or security
software which fails to properly disable Windows Defender.

What antivirus do you have installed?

Several of the major antivirus vendors--I think both Symantec and McAfee,
have knowledge base articles about this issue and how to resolve it.

One method is to run the services control panel applet, and set Windows
Defender startup to disabled.


As a "quick fix," I ok to error message, go to task manager and under
"services" tab go to Windows Defender, right click and choose start service.
So far, this has worked. All updates and scans "seem" to be going through.
This problem only started after I changed my virus protection to McAfee. I
hope this works for you as well. I don't plan on using this temp fix long,
but until I can get through to either cust support, it's better than no
Defender at all.

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