this is NOT a solution!!!
when u do this, windows defender will NOT start-up when u boost up your pc!!!! but it's still not working. the only thing that happend is you don't get an error message. but when u wish to start up windows defender, you get the same error. and u need windows defender!!!
here is an thing that works:
1. go to
control panel
2. click on
System and Maintenance and then click
Administrative Tools
3. select
Service
4. scroll down to
windows defender and double click it.
5. set it to start
automatic when pc boost up
6. click the
start service (or something)
button and wait a second
7. click on
apply and restart your pc
this should work, becouse it does for me... sorry for my bad english, becouse i'm dutch

for the site i used:
My computer did what!: 0x800106ba Windows Defender error in Windows Vista