Help Pls-Can't download 360 demos!!

[analog dog]

I've recently recieved a refurbished 360 since my last one croaked,since then my downloads have just refused to happen,it took me six hours just to download DOOM!!!
When I try to download demos it chuggs to about 2% and then gives me an error saying this cannot be downloaded.
I have my 360 running via a USB modem not via router using blueyonder as an ISP (in the loosest sense),I've changed the ethernet cable but this doesn't do jack ****,it's really starting to piss me off now as I'm dropping out of games quite frequently.
Now my internet connection is also a bit flaky but I had the engineer out today and he reckons all is good with the connection,could it be a virus?
Sorry for rant but I'm getting a bit worried now.
Many thanks in advance for any ideas

[fahrenheit]

So the PC gets its broadband from the USB modem and then you have an ethernet cable going out of the PC to the 360?

What is you NAT status when you do the Xbox Live connectivity test in the systems blade?

Forward these ports:

3074 UDP and TCP
88 UDP
3330 UDP
53 UDP

[analog dog]

many thanks for the info mate,much appreciated.
I went to the network settings and checked the NAT settings section but it wasnt entirely clear as to where I should do the forwarding.
I'm not very savvy when it comes to stuff like this any other info would be great.
thanks again

[fahrenheit]

The forwarding is done in the modem/routers software. You'll have to work out how to access your routers configuration page (you type the ip address into a web browser ie http://192.168.0.1 and enter the user name (usually 'admin') and password.

Have a look for your router here http://www.portforward.com/english/r...outerindex.htm
and you will find clear instructions how to forward the ports that I've given you.

[analog dog]

damnit my modem is not on that list.
called xbox and they blame the ISP,I think ive got a virus on my computer any ideas for a way to find out?
cheers

[EvilBoris]

Try turning off any firewalls on your computer and see if it works then

[babs]

I think ive got a virus on my computer any ideas for a way to find out?

Run a virus scan, if you don't have a scanner grab AVG Free or Antivir or any other free one.

[analog dog]

cool cheers downloading avg now
can we speak to english xbox support?the number on the website goes to america

[bootmonster]

check your cable mate, had similar problem and it was my crossover cable playin silly fukers.brand new one works fine.

[Robster]

cool cheers downloading avg now
can we speak to english xbox support?the number on the website goes to america

Afraid not mate, you can email them from xbox uk page if that helps.

[analog dog]

wow i ran AVG and had 88 ****in trojans!
and various other bad looking ****e.
anyway cleaned that up but the problem still remains
spoke to support and they blame my ISP,spoke to my ISP and they blame my PC!
2 1/2 years I had live without one single problem and now i'm ****ed,thing is i can't figure out whether its just a coincedence that Ive got a new box that isnt working or whther its my ISP,I feel like alcoholic that can only drink water at the moment.....

[bootmonster]

try creating a fresh install on another drive/partition see if that makes a difference.

rule out software. the nic port on either could be damaged tho, not uncommon.

[analog dog]

thanks agaiin for the continued help
I ran avg but it is not allowing me to fix some problems bcause'files are contained in the archive and are unable to be fixed.
I'm getting desparate now,is it worth taking to PC world healthcheck or get a PC doctor out to see it?