It's no longer possible to change the MSDN/TechNet profile association to a different microsoft account.
https://social.technet.microsoft.com/wiki/contents/articles/4806.how-to-change-your-email-or-live-id-on-an-msdn-or-technet-profile.aspx
When you create an MSDN forums profile it is associated to a microsoft account. The microsoft account is only used for the authentication method. What you can do is create and alias on your microsoft account with the new email address and then sign on with
that address.
https://support.microsoft.com/en-us/help/12407/microsoft-account-manage-aliases
Regards, Dave Patrick ....
Microsoft Certified Professional
Microsoft MVP [Windows Server] Datacenter Management
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