dash.exceptions.IncorrectTypeException: The output argument [...] is not of type `dash.Output`

Hi, I’ve been scratching my head over this bug for an hour now. I have the following callback function:

    [Output("average_table", "data"),
     Output("average_table", "columns"),
     Output("worst_table", "data"),
     Output("worst_table", "columns"),
     Output("worst_0", "data"),
     Output("worst_0", "columns"),
     Output("worst_3", "data"),
     Output("worst_3", "columns"),
     Output("worst_5", "data"),
     Output("worst_5", "columns"),
     Output("worst_6", "data"),
     Output("worst_6", "columns")],
    [Input("upload-data", "contents"),
     State("upload-data", "filename")]
def updateTables(contents, filename):
    if contents is None:
        raise PreventUpdate
    av, wo, st0, st3, st5, st6 = parseData(contents, filename)

    return av, columns, wo, columns, st0, columns_w, st3, columns_w, st5, columns_w, st6, columns_w

which trows the error seen in the title of the Topic. I’ve looked a similar posts on this forum and could’nt find anything. If I overlooked something, a pointer would be nice :smiley:


Traceback (most recent call last):
  File "E:\Dokumente\DCDM Dashboard\app.py", line 140, in <module>
  File "E:\Dokumente\DCDM Dashboard\venv\lib\site-packages\dash\dash.py", line 879, in callback
    self._validate_callback(output, inputs, state)
  File "E:\Dokumente\DCDM Dashboard\venv\lib\site-packages\dash\dash.py", line 666, in _validate_callback
    raise exceptions.IncorrectTypeException(
dash.exceptions.IncorrectTypeException: The output argument `[<dash.dependencies.Output object at 0x0000012C13B237F0>, <dash.dependencies.Output object at 0x0000012C13B23AC0>, <dash.dependencies.Output object at 0x0000012C13B23B80>, <dash.dependencies.Output object at 0x0000012C13B23BE0>, <dash.dependencies.Output object at 0x0000012C13B23C40>, <dash.dependencies.Output object at 0x0000012C13B23CA0>, <dash.dependencies.Output object at 0x0000012C13B23D00>, <dash.dependencies.Output object at 0x0000012C13B23D60>, <dash.dependencies.Output object at 0x0000012C13B23DC0>, <dash.dependencies.Output object at 0x0000012C13B23E20>, <dash.dependencies.Output object at 0x0000012C13B23E80>, <dash.dependencies.Output object at 0x0000012C13B23EE0>]` is not of type `dash.Output`.

Hi @titusA and welcome to the Dash community :slight_smile:

I don’t see anything wrong with the callback you posted. Do you get a similar error with other callbacks - or if you run one of the examples from the tutorial?

yes I did try that and got the same error. I don’t know why exactly but resetting my python enviorment did the trick. I was trying to compile my dash app into a standalone exe and totally bricked my app. The callback is working again but I still don’t know how to go about the exe problem…