DATAMART (PREVIEW) CdsaMashupUserException

Hi Alefato ，

This error is commonly triggered when a step makes a direct reference to a column name that doesn't exist in the query.

Example: You have a query from a text file where one of the column names was Column. In your query, you have a step that renames that column to Date. But there was a change in the original text file, and it no longer has a column heading with the name Column because it was manually changed to Date. Power Query is unable to find a column heading named Column, so it can't rename any columns. It displays the error shown in the following image.

There are multiple solutions for this case, but they all depend on what you'd like to do. For this example, because the correct Date column header already comes from your text file, you can just remove the step that renames the column. This will allow your query to run without this error.

Additionally, we recommend that you take a close look at the error reason, and error detail to understand what's causing the error. You can select the Go to error button, if available, to view the first step where the error occurred.

Refer to the similar thread:  Expression.Error: The column '' of the table wasn'... - Microsoft Power BI Community

Best Regards,
Community Support Team _ kalyj

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