Web Service uses ASPNET user although changed to administrator user in IIS

[okaminer]

Hi
My problem is this
In the Website (of my webservice) in the IIS, I've changed the ASPNET
user in the Directory Security to administrator user, And restarted
IIS.
Yet when running the web service it still get security error which says

I'm running it with ASPNET user.


Does anyone have any idea why it is happing
Any cache in the IIS that need to be restarted other than just
restarting the IIS itself?