The "Unexpected error" message when trying to schedule an exam (such as AI-900) is typically caused by an issue on the Pearson VUE side, often related to the candidate account (for example, a Pearson VUE–wide block after multiple failed payments) rather than the browser or device.
Because incognito mode, different browsers, devices, and clearing cache have already been tried, the next step is to contact Pearson VUE or Microsoft Certification Support so they can check and fix the account status:
- Contact Pearson VUE support directly (chat or phone) and explain that an "Unexpected error" appears when submitting the scheduling form for AI-900. Ask them to check whether there is an ERROR_VUE_WIDE_BLOCK or any other block on the account and to remove it.
- If the issue persists or Pearson VUE confirms no block, open a ticket with Microsoft Certification Support so they can investigate the certification profile and scheduling link.
Once the block or account issue is resolved, retry scheduling the AI-900 exam from the certification dashboard; the error should no longer appear.
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