Connection issues to Azure Analysis Services in Excel - The connection string includes explicit user

Yeah, this is the new Excel build, not Azure. Version 2605 (Build 20026.20168) rolled out June 9, which lines up perfectly with this breaking org-wide. 

What's happening: your first error came from User ID plus an interactive auth hint that the new MSOLAP rejects. You stripped User ID, so now it falls through to the silent token refresh, which fails and throws that ugly generic Error.cpp error instead.

Stuff you can try, in order:

Clear cached creds. Windows Credential Manager, delete anything with asazure or Office/AAD in it, reopen Excel, let it prompt you fresh. Fixes it per-user most of the time.

Switch the connection path. Use Data > Get Data > Azure > Azure Analysis Services database instead of the SQL Analysis Services connector. It handles token caching differently and often dodges the whole problem.

Check every connection in the workbook for leftover Integrated Security=SSPI or any Identity Mode / Interactive Login. Your posted string is clean but check the others.

Roll one machine back to the prior Office build to confirm. If refresh works there, you've proven it's the 2605 regression and you've got a stopgap.

Rolling one box back is your cleanest proof before escalating.

If this helped, a thumbs up and accepting the solution would be appreciated.

Best,
Shai Karmani

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