QUOTE(marcozd @ May 5 2009, 02:56 PM)

Why all of a sudden would this be happening?
Difficult to tell. Maybe the NIC on the Xbox has started to fail, and drifted out of tolerance?
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Also, how do I check the duplex status of my computer? I am using Windows Vista Home Premium Edition.
I don't think you can - I was confusing Windows with Linux! Apparently some NIC chip utilities give you this information in Windows, but not all. Probably not worth pursuing if you have another Xbox to try.
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If I take the HDD out of the not working xbox and then install it in a different xbox that I know is working, will that fix the problem?
It might. You'd have to unlock it, then relock it with the eeprom of the new Xbox. You might have to change the kernel version in the softmod to match the destination Xbox kernel before doing the unlock and swap.
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And if I have the same problem can I assume that it is a software issue and not the xbox itself?
It's unlikely to be a software issue because changing the network connection fixes the problem. I'd do the swap first, rather than trying to second guess the cause of one of the possible outcomes.
QUOTE(Heimdall @ May 6 2009, 12:12 AM)

Maybe it's the NIC on your PC?
The easiest way to tell if it's the software is to put a clean copy of UnleashX into a temporary directory, boot with Frosty's rescue disc (to load a different BIOS), then use the file manager to run your temporary copy of UnleashX. If it works then the problem is your current software, if it doesn't then it's your hardware - the Xbox, the PC, or the cable, or some horrible interaction between the three.
Hey.
It turned out that it was the software for some reason. I copied a fresh version of XBMC into a temporary directory on E by hooking my xbox up to the router and using DHCP settings.
Then used Frosty's Rescue disc, went to the file manager and started up my fresh XBMC. I set it to static IP address and BAM! worked like a charm.
So my final fix was to completely remove my old XBMC directory and copy over a fresh version. I think it is because I use XBMC as my default dash and I was running the unleashX dashboard as a program after booting into XBMC that unleashX ftp was also not working.
Go figure. I am up now and I just wanted to say a HUGE thankls to Heimdall and Bomb Bloke for all of their help.
Cheers!