Formula.Firewall error with invoked function on named range of Excel Sheet

Hi Watever ,

Based on your description, the Formula.Firewall error you are experiencing may be due to the privacy level setting of Power Query, which protects the privacy of your data by preventing unauthorized combinations of data from different sources that could expose sensitive information. When you use a custom function, Power Query treats it as a separate data source. The privacy levels of these data sources may conflict, resulting in Formula.Firewall errors.
You can try modifying the merge privacy level rules in excel.Data -> Query Options ->Always ignore Privacy Level settings.
Or combine data sources in a single query instead of using a custom function, which avoids privacy level conflicts.

let
    GetValue = (rangeName as text) as any =>
    let
        Source = Excel.CurrentWorkbook(){[Name=rangeName]}[Content]{0}[Column1]
    in
        Source,

    ID_WH = GetValue("ID_Warehouse"),
    #"Filtered Rows1" = Table.SelectRows(#"Changed Type", each [Entrepot] = ID_WH)
in
    #"Filtered Rows1"

Privacy levels in Power Query - Power Query | Microsoft Learn

Best regards,
Albert He

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