Data / model

Processing error: Type Mismatch

Power BI dataset refresh error: what it means and how to fix it.

What this means

An M-script data-type mismatch during processing (often a stale Power BI Desktop version).

How to fix it

  1. Fix the M type conversion that is mismatched.
  2. Update Power BI Desktop and republish.
  3. Retest the refresh.
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Frequently asked questions

What does the "Processing error: Type Mismatch" error mean?
An M-script data-type mismatch during processing (often a stale Power BI Desktop version).
How do I fix it?
Fix the M type conversion that is mismatched. Update Power BI Desktop and republish. Retest the refresh.
Where does this Power BI refresh error appear?
It appears in a Power BI semantic model's refresh history when a scheduled or on-demand refresh fails.

Related data / model errors

Catch this automatically

RefreshRadar monitors every Power BI dataset refresh and emails you when one fails, with the likely cause and the fix, so you are not hearing about a broken refresh from your stakeholders first.