How to identify which column is causing OLE DB or ODBC error: [DataFormat.Error] We couldn't convert

Anonymous , Open Power Query, click on Source step follwed by ramining steps, click on Step-by-Step in Applied Steps in right side. If you see the table each and every step, then that step is not having issue. Mostly, You can will see the issue in Changed Type or Custom Columns

Hi Anonymous ,

Here's a step-by-step plan to troubleshoot the issue:

1. Check Data Types: Ensure that the data types in Power BI match the data types in the data source. Data type mismatches are common causes of such errors.

2. Binary Search Method:
- Duplicate the query causing the error.
- Use a binary search approach by removing half of the columns and then applying the changes. If the error persists, the issue is within the remaining columns. If not, the issue was in the removed half.
- Repeat this process by halving the number of columns until you isolate the problematic column.

3. Use the Query Diagnostics:
- In the query editor, go to the "Tools" tab.
- Click on "Query Diagnostics" to start a diagnostics session.
- This can help you identify which step is causing the issue.

Best regards,
Community Support Team_Binbin Yu
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