There's a mix of issues here, it seems to me.
Was Norton/Symantec already installed before getting service pack 3?
When was SP3 applied? and did you take pre-installation precautions prior to the SP update? That last is very crucial.
You must temporarily disable any antivirus & malware app from active monitoring prior to and during SP update. And also, pretty much the same during Internet Explorer upgrade.
Which was applied first: XP service pack 3 or I.E. 7 ?
There is an issue with Norton/Symantec, which has been reported in various venues.
See XP SP3: Registry Corruption & Norton SymProtect
http://aumha.net/viewtopic.php?f=62&t=33522
I'd urge you to check that out.
--
Maurice Naggar
MS-MVP (Windows Client) , Aumha.net VSOP , DTS-L
-----
"shadow" <shadow@discussions.microsoft.com> wrote in message news:E241986E-571A-4D00-BF48-FAC2CB40B5C6@microsoft.com...
> when upgrade to ie7,after my system disables automatic update service,I
> restart and check the service I found it disabled ,I try to run the service
> it runs ok in the begining,then as soon as I use my explorer to open file or
> drives the service gets disabled,and I fail to start it until I restart
> agin,and also my internet security settings are altered to low level
> security,each time I reboot,I'm not realy sure if it's an ie7 error or is it
> the sp3 ?I have norton internet security 2008 installed and I perform all the
> pre-installation precedures