Hi Don-Bot 

That error means the dataflow is trying to write a column whose values are not a supported primitive type for Lakehouse tables. In your case, the message "We cannot convert the value 0 to type Function" points to a column that ended up with values of type Function (often from a custom step that returns a function instead of invoking it). Lakehouse tables only accept primitive types (text, number, datetime, etc.) and explicitly do not support Function, List, Record, or Table values as column values. See supported types and destination behavior in Microsofts doc: Dataflow Gen2 data destinations and managed settings.

Quick solution

1. In Power Query Online, verify every column is a primitive type before the destination step. Expand or convert any List/Record columns and remove any columns whose values are Function.
2. If you are landing in an existing table, align data types and nullability to the destination. If necessary, temporarily switch to Replace with dynamic schema or recreate the table after fixing types.
3. For Salesforce specifically, expand relationship and complex fields (they often come in as Records or Lists) and cast to nullable primitive types.
4. Republish the dataflow and reconfigure the destination mapping if you changed schema.

Common Salesforce gotchas
Relationship columns like Owner, CreatedBy, Account often arrive as Record. Use the expand icon to select fields like Owner.Id or Owner.Name.
Multi-select picklists or arrays can arrive as List. Expand to rows or transform to text (for example, Text.Combine(List.Transform([YourList], each Text.From(_)), ",")).
Connector references: Salesforce Objects connector in Fabric and general Power Query connector notes: Power Query Salesforce Objects.

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