Any help anyone can provide would be great.
Get your users to provide a description of the problem that is better than this:
The users are complaining of having no internet access on their workstations. Some users are reporting that "some" websites are working while others are not.
This is a wholly inadequate problem description. If this is what they
are telling you, then you should turn around to them and have
them describe their problems to you properly. One
must
follow the standard litany for problem reporting. One
wouldn't go to a doctor and tell xem "Doctor, I have a pain in some of
my legs.". It begs the response "Don't be obtuse! Which leg
is the pain in?".
If you want help from us, in turn, you're going to have to follow
the standard litany here, too, with all of the precision that it
requires. Which WWW sites? What, exactly, does
"not working" mean? How do you even know that this WWW browser issue
is a DNS problem at all? Prove
that
it is.