This article is from the AmiTCP/IP FAQ, by Mike Meyer with numerous contributions by others.
This is a routing problem. Add a route to your default gateway using the command:
AmiTCP:bin/route add default your.default.gateways.number
140.174.153.10 is my default gateway. Ask your system administrator for this number. This command should be already in your startnet script if you have followed the Install procedure correctly.
This could also be because of a firewall (the IP traffic from your hosts is not passed to the Internet). Your Network provider will be able to give you more information on this.
 
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