Unable to complete network request to host

[tryanderror]

I ran into a strange error.
First I tried to install Zeos on another machine with windows XP and Delphi 2007. I always get this error on that machine and nothing that is related to this topic I found in ther forum would help.

So I tried another machine and everything works fine.
Yesterday I tried to install a VPN Connection but this failed.
After that I get the same error as on the other machine.

Maybe anyone know how to fix this.
I think it is related to the network settings on the machine.

Windows XP Professional SP2, Delphi 2007

Error: unable to complete network request to host "localhost" Failed to establish a connection