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I'm pretty confused now. I'm pretty sure I haven't tampered with my console, participated in any online fraud or repeated in egregrious violations.
"To protect the Xbox LIVE service and its members, Microsoft does not provide details about console bans. " - Microsoft. This means they won't tell me why exactly I've been banned and furthermore there isn't a support forum for console bans (only account bans). I've no idea what to do and they say that there is no recourse for console bans.
There was one thing that happened the day before the banning (31st Aug) though. I was invited to an XBL party by someone who I've never seen/played with on XBL. I was curious so I joined. Once I was in, another person in the party listed my Location and ISP. They did the same for someone else who has just joined the party. They also knew my IP address. I left the party after that though, as it all seemed pretty suspicious. I'm pretty sure they had a jtagged Xbox because I can't see any other way they'd be able to do that.
I'm not sure if it was because of something that user might've done, or just a mistake by Microsoft, but my console's been banned. Any advice is greatly appreciated.