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If trial and error doesn't help, please post more information on the hardware. What type of laptop? Is this booting from the CD or the hd? Do you have the network settings configured correctly (run 'netcardconfig')? Try and see if the card is recognized (use the command 'cardctl'). Check to see if you have the correct modules installed (use the command 'lsmod' and also check what is listed in /etc/modules). Finally, check the system messages to see what, if any, errors are seen (run 'dmesg').