Excel Power Query / Azure Analysis Services: Authentication failed after reopening workbook, no Entra login prompt shown

Hi @Kateryna Kravchenko , @Manoj Kumar Boyini
The issue still persists in Version 2602 (Build 19725.20170) despite following the recommendations provided above. The Power Query/Azure Analysis Services authentication bug remains unresolved. Any other views?

Hi @Manoj Kumar Boyini , Krzysztof ‪‪‪‪‪Loda,
I have just received the update to Version 2602 (Build 19725.20170), but unfortunately the issue still persists on my side.

I tested it with two colleagues on the same version and build: for one of them, the issue does not occur, for the other, the issue is present.

So, I assume it might not be related to the version.

Hi @Kateryna Kravchenko

Thanks for the detailed update - this really helps narrow things down.

Based on what you’ve tested (including across users on the same version), this doesn’t look like a simple version issue anymore. What you’re seeing is consistent with how Excel Power Query handles Entra ID tokens for Azure Analysis Services - specifically, it tries a silent token reuse after reopening the workbook, and if that fails, it doesn’t always trigger a fresh login prompt.

A couple of observations from your findings:

• Since Power BI Desktop works fine and Excel “Analysis Services” connector also works, this is likely limited to the Power Query + SQL Server Analysis Services connector path
• The inconsistent behavior across users on the same build suggests it’s tied to local token cache / Office identity state, not just Excel version

At this point, here are the most practical things to try:

• Try switching (where possible) to Data → Get Data → From Analysis Services instead of the SQL Server Analysis Services connector — this path uses a slightly different auth flow and is generally more stable
• Fully clear cached credentials, not just in Data Source Settings, but also from Windows Credential Manager (MicrosoftOffice / ADAL entries), then reopen Excel and reconnect
• Sign out of Office completely (File → Account → Sign out), close all Office apps, then sign back in
• Check if the issue reproduces in a clean profile or another machine - this helps confirm if it’s cache/profile related

One important point: Right now, there is no reliable way to force Power Query in Excel to always prompt for login when the token reuse fails - this behavior is handled internally by the MSOLAP/Office auth stack.

Given multiple users are seeing this, it’s likely a known limitation/bug in Excel’s Power Query authentication flow with AAS, rather than anything misconfigured on your side.

If this continues to impact your workflow, the most stable alternatives today are:

• Using the Analysis Services connector in Excel (non–Power Query path)
• Or using Power BI Desktop for ingestion scenarios

If you’re open to it, I can also help you validate whether your connection setup can be adjusted to avoid this path altogether with minimal changes.

Thanks again for the detailed investigation - that was really helpful.

Hi @Smaran Thoomu ,

Thank you for the thorough response.

I have a significant update. I've since been updated to Version 2602 (Build 19725.20170), which is the same version my colleague is on. The issue persists for me, but not for him. To isolate further, we ran a test: my colleague logged into my laptop with his account and tried to refresh the same workbook (shared via OneDrive). He experienced the exact same failure: credentials work after manually re-entering them, but the token doesn't persist across sessions. On his own laptop, the same file refreshes without any issues.

This confirms the problem is machine-specific, not tied to user profile, Excel version, file, or AAS configuration.

Regarding your suggestions:

• I've already confirmed that the non-Power Query path (Get Data >> From Database >> From Analysis Services) works reliably across sessions on my machine. However, this only provides a PivotTable/Power Pivot view, I need Power Query import mode so users can apply transformations, which is where the authentication fails.
• I've tried the full credential cleanup (Data Source Settings, Credential Manager, Office sign-out/sign-in cycle) multiple times. It resolves the issue temporarily, but the token never persists across a close/reopen cycle.
• The clean profile test effectively happened when my colleague used his account on my machine, same result.

Knowing that this is a machine-specific issue, could you recommend additional steps on how to resolve this?

@Kateryna Kravchenko Thanks for taking the time to isolate this so thoroughly - the test you did (same file + different user on the same machine) is especially helpful. That clearly points to a machine-level issue, not user, version, or AAS configuration.

Based on what you’ve described, this is most likely related to how Excel Power Query is storing or reusing Entra ID tokens on that specific machine (Office identity cache / Web Account Manager / local auth components).

Since you’ve already tried the usual credential cleanup, here are a few deeper things that are worth checking:

• Try a full Office sign-out + reset of identity cache
  • Sign out from all Office apps
  • Close all Office processes
  • Then remove cached identities from:
  • Windows Settings → Accounts → Access work or school (disconnect and re-add)
  • Reopen Excel and sign in again
• Check if this reproduces in a new Windows user profile
  • This helps confirm if it’s tied to the OS profile rather than the machine globally
• Verify if there are any group policies or security tools on that machine
  • Some environments clear or restrict token persistence (WAM/ADAL), which can cause exactly this behavior
• As a quick validation, test from:
  • Another network (non-corporate, if possible)
  • Or temporarily without VPN

One important takeaway from your findings: Since the Analysis Services (non–Power Query) connector works consistently, and only the Power Query path fails to persist tokens, this does point to a limitation/issue in the Power Query + Excel auth flow rather than Azure Analysis Services itself.

At this point, if the behavior continues even after the above checks, it would be reasonable to treat this as a client-side issue specific to that machine, and we may need to involve the Excel/Office team for deeper investigation.

If you’re able to try the new Windows profile test, that would be the most useful next signal - let me know how that goes and we can take it from there.