I have freshly installed VS2010 with SP1, and when I try to connect to a project on tfspreview.com, I get TFS31002 error:

Google did not help very much. Anyone solved this?
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Ok, I managed to find this blog post which has solution: install KB2581206 which enables VS2010 to connect to tfs-azure and use Microsoft account to authenticate.
It works 🙂
Credits to Tarun Aurora