Vista cannot obtain an IP address [solved]

Referring to my thread http://tinyurl.com/64p9ew it works for one day
then I get again the same problem. I found (finally) the solution... I
have changed in
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic es\Tcpip\Parameters\Interfaces\{GUID}
some parameters like mentioned in
http://support.microsoft.com/default.aspx/kb/928233

After ipconfig /renew my PC gets from the DHCP server (Zyxel 2602) an
ip-adres. Solution is reproducible because after some reboots my Vista
PC gets a regular IP address, like XP before and my wife's Linux PC :-)