That could most defaintly be a cause, but how to set it back again is a very good question.
Try disabling it this way :
DISABLE ::
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic es\Tcpip\Parameters] "IPEnableRouter"=dword:00000000
ENABLE ::
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servic es\Tcpip\Parameters] "IPEnableRouter"=dword:00000001
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I suggest making a backup of your registry b4 trying this, and dont come back here hitting my head if it screws up
If this fails, go get your router