Persistent HTTP 500/502/503 from Microsoft Graph To Do endpoints for a personal MSA

Escalate this through Microsoft’s personal-account support channel and include the Graph correlation data plus the To Do Session and User ID, because account/backend repair cannot be performed from Microsoft Q&A.

Open the support case

1. In Windows, open Get Help while signed in with the affected personal Microsoft account.
2. Enter: Microsoft To Do personal account — persistent Graph 500/502/503 and Windows sync failure.
3. If automated troubleshooting does not resolve it, select Contact Support.
4. Choose the closest available Microsoft To Do, Outlook.com, or Microsoft account product category, select Confirm, and request chat or a callback. Contact options vary by product, time, and subscription.^1^
5. In To Do for Windows, select profile picture → Settings → Copy Session and User ID. Include that value privately in the support case, not in this public thread. Microsoft specifically requests these identifiers for To Do support reports.^2^

Ask support to route the case to the team responsible for Microsoft To Do/Outlook task storage and Microsoft Graph, and to investigate the affected account’s service state. “Backend provisioning” is a reasonable investigation request, but the available evidence does not establish provisioning as the root cause.

Include this diagnostic packet

Provide:

• Affected account type: personal Microsoft account (@outlook.com).
• Graph client ID and authentication flow.
• Delegated scopes: Tasks.ReadWrite User.Read.
• Exact failing operations:
  • GET /v1.0/me
  • GET /v1.0/me/todo/lists
• Status sequence: persistent 500, 502, and 503.
• Response body: UnknownError with an empty message.
• Exact timestamps in UTC for representative requests.
• The corresponding:
  • Graph response request-id
  • response Date
  • client-request-id, if one was sent
  • complete x-ms-ags-diagnostic value
• To Do Session and User ID.
• Windows To Do version and the indefinite Syncing… symptom.
• The fact that To Do web/mobile can read the existing data.
• The completed authentication, transport, DNS, TLS, client, and network tests, so support does not repeat them.
• The related Q&A case links already collected.

For any fresh capture, send a unique client-request-id GUID and save it with the response request-id and Date; Microsoft identifies these fields as necessary for support correlation.^3^

GET /v1.0/me/todo/lists HTTP/1.1
Host: graph.microsoft.com
Authorization: Bearer <redacted>
client-request-id: <new-guid>
return-client-request-id: true

Do not post the access token, Session/User ID, full account address, or other account identifiers publicly.

Technical assessment

GET /me/todo/lists is documented for delegated personal Microsoft accounts. Tasks.Read is sufficient and Tasks.ReadWrite is also supported, so the stated permission set covers this operation; success should return 200 OK and the list collection.^4^

The repeated 5xx responses indicate that a server or gateway failed to complete requests that appeared valid. A 502 can be retried when the operation is safe, while a 503 should honor Retry-After when present. Persistent failures should not be probed continuously; use bounded exponential backoff and stop after several attempts.^5^

No public Microsoft notice supplied here identifies a To Do-specific incident matching the reported time window.^6^ The referenced /me/todo/lists reports also have no accepted or recommended resolution, so they support correlation but do not document a self-service repair. The mix of Graph failures and Windows sync failure warrants service-side investigation, but it does not by itself prove that the account’s Exchange/To Do provisioning is damaged.

While awaiting support, web/mobile can remain the operational workaround because they can currently display the data. Avoid deleting lists, resetting the account, or recreating data unless Microsoft Support explicitly requests it; those actions could complicate correlation or risk data loss.

References

1. Get Help for Microsoft personal account users | Microsoft Support
2. Give feedback on Microsoft To Do | Microsoft Support
3. How to debug Microsoft Graph API calls
4. List lists
5. 500, 502, 503, and 504 errors from APIs: what they mean and how to handle them
6. Microsoft service health status