I'm trying to add a gold 3 month subscription that is on sale on the Xbox 360 Dashboard. Every time, even after restarting my console, I get this error. The website has a different error for trying to add a one month gold sub. I just want to play Xbox Live, any suggestions?
That code usually means you have some sort of billing violation on your account. Go to https://billing.microsoft.com and make sure everything is correct and up to date. If you can't fix it there, you'll need to call support and talk to billing to have them help you sort it out.
It means that you have a past due balance on your account. Most likely you had a credit card subscription prior to this one and it automatically renewed with out you realizing, and was not able to charge your card. Call support and have them remove the past due balance.