Restricted Sites problem in Internet Properties ( Vista Home Premi

The slider in Internet Properties/Security Tab/ Restricted Sites on my
'puter is set to High and the check-box for Enable Protected Mode is ticked,
but for some unknown reason if I look at these settings later ( I have no
specific time cause it varies, and I can't determine when it happens, whether
surfing or gaming, etc ) I'll notice that the level has automatically changed
to the Custom Level and various boxes are ticked or un-ticked, after I notice
this I usually just hit the Default Level button and it returns to High, then
I click Apply,then Ok, and return to whatever I want to do. But again later
(undetermined) it will change again.
Why does this happen ???

(BTW, I'm the only user of this Computer, it's in my home office, very
secure and I'm very meticulous about my security and security programs and
scans)
Thanks for any help ...

 

That should only occur on sites in the Restricted zone.
Are you in the Restricted zone when you do this?

Check your zone?

 

Thanks for amswering ... I have no idea whether I'm in a Restricted Zone or
not most times, because most web-sites ( even legit, known good ones ) have
links or some aspects that are considered restricted by IE, but I will keep
an eye on my surfing habits a little closer to attempt to see when this
change to the Security settings occur.

The only url I have in the restricted sites zone is ( *.google.com, as an
experiment, yes I know it's broad because of the * )and I do google quite
frequently, this may be the reason, but this also means that any site that I
go to that may be restricted ( but is not listed in my sites list ) can
automaticaly change my settings without my permission, this shouldn't be, is
this fair to assume ?

To add : I notice that sometimes a security pop-up will appear telling me (
when I click on a link or attempting to move to another page) that I'm moving
away and then I get a yes or no check-box in order to do this... will this
change my setting because I have agreed by clicking on this yes box ???