DIAL-UP NETWORKING DID NOT INSTALL FOLLOWING XP UPGRADE FROM WIN 2000P

I recently upgraded my PCs in my network from Windows 2000P to Win XP(P).

After the upgrade, dial-networking did not install in some PCs. I detected this in the PCs that run dial-up services in addition to DSL. In the course of troubleshooting, I discovered that the ‘remote access connection manager’ service in computer manager would not start automatically.

Could this be the cause of the problem? When I clicked to start it manually, I got the response ‘access denied’.

I would not want to lose the mail in my mail folders if I have to do a fresh installation. What do I do?