Sorry you're having issues getting your preview system message. First and foremost please do not post any personal information in the forums including service request numbers. Also, even though you've been invited does not mean that you've been accepted.
If you still haven't received your system message, I would request posting in the forums below. If you receive group not found, then post back and let us know. Usually within a couple of days a moderator will give you access based on your account needs.
Preview Program Support Forums
MCP. MCDST. LVL 80
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