Project 2003 unable to connect to the project server

[HB]

Guys,

Please help me regarding the following:

I have a workgroup LAN all of the PCs is working fine from the web access
but only 2 PCs is able to establish a connection to the project server.
all PCs is XP pro, all have same configuration as well.

If I try to access using the prevented users access credentials on the
working PCs it work fine, so no problem with access credentials.

Error MSG keep popping:
"project was unable to establish a connection with selected project server.
This could be caused by a loss of network connectivity, invalid user name
or password, lack of an enterprise global template, or problems with project
server or database, or your project server may not have enterprise features
enabled"


PLEASE HELP

thanks

HB