Power Query Refresh Failing After Source File Structure Changed

Hi Mohit009​,

You can handle this in Power Query by standardizing the column name and renaming the variant to the expected name.

= Table.RenameColumns(
    #"Promoted Headers",
    {
        {"CustomerID", "Customer_ID"},
        {"CustomerName", "Customer_Name"}
    },
    MissingField.Ignore
)

In the above query, Power Query checks for the CustomerID and CustomerName columns and renames them to Customer_ID and Customer_Name, respectively, if they exist. If either column is missing, it simply ignores it without throwing an error.

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Hi Mohit009​ 

You can handle this automatically in Power Query by standardizing the column names in the Transform Sample File query.

Add a step immediately after the source/navigation step, before any transformations that reference the column:

= Table.RenameColumns( #"Previous Step", {{"CustomerID", "Customer_ID"}}, MissingField.Ignore )

This way:

• Files containing CustomerID will have the column renamed to Customer_ID.
• Files already containing Customer_ID will remain unchanged.
• Subsequent transformation steps can consistently reference Customer_ID.

Since you're using Combine Files, make sure this logic is applied in the transformation function used for each file, not just in the final combined query.

Also, check the automatically generated Changed Type, Removed Columns, and Expanded Table Column steps, as they may still reference the old structure.

One important consideration: this handles known naming variations, not arbitrary future column changes. For a more robust solution, I would recommend standardizing the source file schema whenever possible.

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