Can't Connect to Xbox Live. MTU Issue.

[ElDiabloRobotico]

a couple of days ago i turn on my 360 and it shows i am disconnected from xbox live. i run a test and it says my MTU settings are too low, needs to be at least 1324 (i think). never been an issue before and i didn't change any settings on my router or xbox prior to this error. i changed my MTU settings (tried a few different numbers between 1324 and 1500). still won't connect. i remove the router from the equation and hook up the 360 directly to the modem and i still get the same error. any suggestions? seeing as how i didn't change any setting before this issue came up, could it be something that my ISP did? i'm not gonna lie, guys... going a bit nutty without my online gaming fix

other info:

my 360 is directly connected to the router via ethernet cable (not wifi)

everything else the connects to my network works fine (computer, cell phones)

[lazyworm]

Can you describe more about this test? Do you have trouble
getting to the internet in general? Who is your ISP?

MTU value issue is generally between your home router and your ISP.

[lazyworm]

Obviously I don't own an Xbox. If this is the test on the Xbox, google
show a lot of hits...

http://www.google.com/search?q=xbox+mtu

[1Fastrider]

If you're plugged directly into the ISP hardware (not home router) you'll probably have to take it up with them.

[ElDiabloRobotico]

Can you describe more about this test? Do you have trouble
getting to the internet in general? Who is your ISP?

MTU value issue is generally between your home router and your ISP.

if your xbox can't connect to xbox live it ask you if you want to run a test to see where the problem is. it shows i can connect to my network just fine but from there it can't connect to the internet and i get the "low MTU" message.

i'm using ACS, my only choice unless i want dial-up.

and i don't have problems connecting any other device to my network and accessing the internet.

Obviously I don't own an Xbox. If this is the test on the Xbox, google
show a lot of hits...

http://www.google.com/search?q=xbox+mtu

yeah, looked at all those and tried a bunch of different things. none of them worked

If you're plugged directly into the ISP hardware (not home router) you'll probably have to take it up with them.

that's what i thought. gonna give them a call. that should be as fun as pulling teeth.