I have been using Mepis on a dual boot computer for over a year. I want to give ubuntu a try so I made a bootable usb stick from ubuntu's live cd. Everything works as advertised even saved files and changes.

THE PROBLEM

I can't connect to the internet

I am connected via a 2wire modem to a linksys router thats connected to my computer through a ethernet cable. the router is for connecting my son's computer.
Anyway I have no problems connecting from windows or Mepis.
Whats strange is I can even connect when booting directly off the Ubuntu live CD. When I try connect when booting from my usb stick I get a can not connect error
I am using the auto eth0 function and everything appears fine. I compared my settings from when booted from the Ubuntu live CD and they are Identical.
I used network tools and I can ping my IP address but when trying to ping a web address I get the can not connect error. I am beginning to think ubuntu has my USB stick confused with a CD but not sure how to correct it. HELP

Here's some additional INFO:

ubuntu@ubuntu:~$ ifconfig
eth0 Link encap:Ethernet HWaddr 00:1c:25:6f:b2:70
inet addr:10.10.10.100 Bcast:10.10.10.255 Mask:255.255.255.0
inet6 addr: fe80::21c:25ff:fe6f:b270/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:162 errors:0 dropped:0 overruns:0 frame:0
TX packets:62 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:104139 (104.1 KB) TX bytes:6945 (6.9 KB)
Interrupt:27 Base address:0x8000

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:80 errors:0 dropped:0 overruns:0 frame:0
TX packets:80 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:9170 (9.1 KB) TX bytes:9170 (9.1 KB)

ubuntu@ubuntu:~$ lspci
00:00.0 RAM memory: nVidia Corporation MCP61 Memory Controller (rev a1)
00:01.0 ISA bridge: nVidia Corporation MCP61 LPC Bridge (rev a2)
00:01.1 SMBus: nVidia Corporation MCP61 SMBus (rev a2)
00:01.2 RAM memory: nVidia Corporation MCP61 Memory Controller (rev a2)
00:02.0 USB Controller: nVidia Corporation MCP61 USB Controller (rev a2)
00:02.1 USB Controller: nVidia Corporation MCP61 USB Controller (rev a2)
00:04.0 PCI bridge: nVidia Corporation MCP61 PCI bridge (rev a1)
00:05.0 Audio device: nVidia Corporation MCP61 High Definition Audio (rev a2)
00:06.0 IDE interface: nVidia Corporation MCP61 IDE (rev a2)
00:07.0 Bridge: nVidia Corporation MCP61 Ethernet (rev a2)
00:08.0 IDE interface: nVidia Corporation MCP61 SATA Controller (rev a2)
00:09.0 PCI bridge: nVidia Corporation MCP61 PCI Express bridge (rev a2)
00:0b.0 PCI bridge: nVidia Corporation MCP61 PCI Express bridge (rev a2)
00:0c.0 PCI bridge: nVidia Corporation MCP61 PCI Express bridge (rev a2)
00:0d.0 VGA compatible controller: nVidia Corporation C61 [GeForce 6100 nForce 405] (rev a2)
00:18.0 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] HyperTransport Technology Configuration
00:18.1 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] Address Map
00:18.2 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] DRAM Controller
00:18.3 Host bridge: Advanced Micro Devices [AMD] K8 [Athlon64/Opteron] Miscellaneous Control
01:07.0 FireWire (IEEE 1394): Texas Instruments TSB12LV26 IEEE-1394 Controller (Link)
01:08.0 Communication controller: Conexant Systems, Inc. Device 2f40
ubuntu@ubuntu:~$ ping
Usage: ping [-LRUbdfnqrvVaA] [-c count] [-i interval] [-w deadline]
[-p pattern] [-s packetsize] [-t ttl] [-I interface or address]
[-M mtu discovery hint] [-S sndbuf]
[ -T timestamp option ] [ -Q tos ] [hop1 ...] destination
ubuntu@ubuntu:~$ ping 10.10.10.100
PING 10.10.10.100 (10.10.10.100) 56(84) bytes of data.
64 bytes from 10.10.10.100: icmp_seq=1 ttl=64 time=0.058 ms
64 bytes from 10.10.10.100: icmp_seq=2 ttl=64 time=0.046 ms
64 bytes from 10.10.10.100: icmp_seq=3 ttl=64 time=0.046 ms
64 bytes from 10.10.10.100: icmp_seq=4 ttl=64 time=0.051 ms
64 bytes from 10.10.10.100: icmp_seq=5 ttl=64 time=0.047 ms
64 bytes from 10.10.10.100: icmp_seq=6 ttl=64 time=0.049 ms
64 bytes from 10.10.10.100: icmp_seq=7 ttl=64 time=0.049 ms
64 bytes from 10.10.10.100: icmp_seq=8 ttl=64 time=0.046 ms
64 bytes from 10.10.10.100: icmp_seq=9 ttl=64 time=0.049 ms
64 bytes from 10.10.10.100: icmp_seq=10 ttl=64 time=0.044 ms

Thanks and Cheers
Wdhpr

in regards to this line:
01:08.0 Communication controller: Conexant Systems, Inc. Device 2f40

Is your default NIC that conexant one? If not you might want to see if it is even detected. Also, did you possibly use a different live CD when making your bootable USB? could be a driver issue. Are you connecting via a dial-up provider such as AOL or do you have DSL or Cable or some other high-speed connection?

Great question concerning conexant. As I stated I am using a 2wire modem connected via a ethernet cable which then connects to my computer also via a ethernet cable. I use the router for a wireless conection to my son computer.
I looked through my system and manuals and found no reference to conexant.

I ran the same system info I listed above from the live CD. It was identical to that when I booted from my USB.
I can connect to the internet from the live CD. Can not connect while booted from the USB. I have no problems as well when using windows and mepis. Stranger still I can send and receive packets to my IP. But I can't connect via my browser nor can I connect via the synaptic update for downloads. Further still while operating from the USB stick my son's computer still has internet access. Weird :O

I also ran the driver checker and all it did was update my nvidia graphics driver. The desktop looks great

Cheers
Wdhpr