It seems like you are experiencing sign-in issues when trying to sign up for the Microsoft Partner Program. One solution to try is to clear your browser's cache and cookies. You can do this by following the steps outlined in the "Clear browsing cache" sections of the Troubleshoot Common Issues and Troubleshoot sign-in issues for Partner Center articles. If this does not work, you can also try resetting your password by following the steps outlined in the "You forgot your password" section of the Troubleshoot account setup or Microsoft AI Cloud Partner Program renewal issues article.
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