Custom Function Error Message

[Anonymous]

Hi, 

I created a function that works in the query editor, but when I "Close & Apply" I get this:

What I have been trying to do is retrieve tracking statuses from a web url. I broke this process down to find out exactly when the messgage occurs, and it seems like it happens as soon as I create the function and save (prior to even evoking it), but only when I insert the parameter into the source table prior to turning it into a function. If I insert the parameter from the Function, it works, but when invoked it only returns the parameter value (It doesn't let me select a column to pass as a value). 

Does anyone know why it works in Query Editor, but returns this error message when I try to apply the changes?

[Anonymous]

Here is the Error Message, it did not attach correctly above

[v-yingjl · Accepted solution]

Hi @Anonymous ,

Have you enabled 'enhanced dataset metadata' option in the preview feature menu?

If so, disable it and try again. There is a limitaion about it:

M expressions containing certain character combinations such as “\n” in column names

Another important point that you should notice is that Enabling the enhanced dataset metadata feature results in an irreversible upgrade to reports.

If you have not backup this file while enhacing this feature, perhaps you need to recreate a new report.

Please refer this document: Desktop-enhanced-dataset-metadata#considerations-and-limitations 

Here are simliar issues that you can also refer that hope to help you:

1. Error Expression in partition 'n/a' in table 'n/a' references unknown variable. 
2. Error on apply Power Query: Expression in partition n/a in table n/a references an unknown entity 

Best Regards,
Yingjie Li

If this post helps then please consider Accept it as the solution to help the other members find it more quickly.

[Anonymous]

Thank you, this seems to have resolved my issue. 

I did have to rebuild the report once disabling the preview feature (I tried doing it from the original report and got the same result), but once I disabled this option and started fresh I no longer got this error message and everything appears to be loading as expected.