Routing and Remote Access Service has disappeared

I am running MS Server 2003 Enterprise Edition, Service Pack 1. My
Routing and Remote Access service has disappeared. When I go to
Administrative Tools, Routing and Remote Access, it gives a MSG Popup
titled Routing and Remote Access, the message is The system cannot
find the file specified. I have found a thread that said to expand
the files dnary.mdb and ias.mdb to the c:\windows\system32\ias folder,
I have tried that several times. When I click OK on the popup window
it takes me to the Routing and Remote Access management console, I
then right click on my server and it shows the option to Configure and
Enable Routing and Remote Access, but when I click this, nothing
happens. When I go to Services, the Routing and Remote Access service
does not even show up. This was working and just stopped. I am not
sure what has happened, and not sure how long it has been since it
stopped, as we do not use the VPN service every day. Does anybody
know how I might correct this issue without reloading the system.
Some of the software I have on this machine is a nightmare to re-
install and get working. Thanks in advance for your help.