Network connections gone

[Guest]

I have a 3 computer network trough a D-link router. The network connections
on the host computer just dissapeared. Hardware is fine, you can view all
computers, workgroups and share files but the internet connection on the
client computers is not working. Internet connection on the host is fine. The
network connection wizard does not work also, the icon is there but nothing
happens when you click it (only this wizard, the others work fine). There is
an error message when trying to open the network connections folder (roughly
translated from spanish) "the network connections folder could not retrieve
the network adapter list on your machine. Make sure the network connection
service is up and running"
Also, in the Computer Management window, in network connection properties
the service status is stopped. If you press start there is an error message
like: "Cannot start network connections services. Error 999: Error executing
indexing operation".
I have not made any changes, software installations etc... the host machine
is almost not used at all. Host uses Windows XP pro SP2 and client Win Xp
Home SP2

 

[Guest]

The problem is solved. I suspected worm or virus influence so I fully scanned
my computer with many softwares, and one came up. After cleaning it, I used
the windows XP CD to repair the instalation (to fix what the worm had done)
and that was it, solved.