Administrator access to workstations in a domain.

I'm the administrator of a 100-user Windows 2003 AD network. Periodically I need to run inventory on all the workstations to verify, among other things, the applications, hot fixes, services enabled or disabled, etc. that are installed on these PCs are current and properly licensed.

I've investigated the various tools that will allow me to remotely attach to the workstations and settled on PsTools from Sysinternals. The two utilties in particular that I've found useful are PsInfo and PsService. These have worked as expected for over 80% of the workstations.
However, I cannot access the remaining 20%. These workstations are used by our developers, programmers, and support staff all of whom have local machine admin permissions in order to develop, install, test, and support our external customers. All of the workstations are Windows XP Pro.

When I attempt to use PsInfo or PsService to query these workstations, the message that displays is "The network name cannot be found." From my research I've found a number of parameters that must be enabled on each remote workstation in order for the PsTools utitilities to function properly. These include:

- The "Workstation" service is running.
- The "Server" service is running.
- The "Admin$" share is available.
- The "Local Security Policy" allows network access by the administrator.
- The "Remote Registry" service is disabled. However, I've used PsService on other workstations to run the "SetConfig" and "Start" options to enable this service remotely.
- Microsoft "File and Print Sharing" is enabled.

I've confirmed that each of the 20 or so workstations comply with these requirements. The only thing out of the ordinary is that the "File and Print Sharing" is enabled but the properties are grayed-out, even to the local administrator's account.

Note that I use the -u and -p parameters to include the Administrator name and password with the PsInfo and PsService commands.

So my questions are:

- Is any other service or security setting responsible for blocking remote access to these workstations.
- What is the meaning of the "File and Print Sharing" being enabled but the properties inaccessible.
- Does a checklist exist indicating all the services, etc. and their settings for the access of workstations on a domain.

Any assistance is greatly appreciated.