[IP 2003] Security problems

[Lp12]

Hi All,
I have a published form running on WSS 2 site.
One user is getting the following error when trying to fill a form: "Your
user name or group membership cannot be verified because the form's security
settings do not permit it".
He could done it in the past but no more.
Any thoughts?
Thanks a lot in advance

 

[Clay Fox]

I would check their IE settings.
All of the security and trust is leveraged from internet Explorer for
InfoPath.