OWA problem

We recently upgraded our website and since then when we try to access owa we get a directory structure view of all employees names. If we click on one of the names we are then prompted for username/password.
Before, when we tried to access owa we were prompted for username/password with no list of names.
This is a security risk as well as an annoyance.

We run iis 6 on server 2003.

Sorry if ive left anything out but has anyone seen this before?

Turns out i have to reinstall exchange...we installed php and apparently this has this effect sometimes!