In Power Query why is Invoke Custom Function when I click on Add a column greyed out?

[Anonymous]

I want to insert a custom column but the function query is greyed out (see screen shot below). In Power Query I click on 'Add Column' then I click on 'Invoke Custom Function' and wizard appears. I can renname the new column name but the next field I can't type anything. If I click on "ok" then a get an explanation mark next to 'Function Query' box and it says to enter a value but I can't?

Any ideas what I'm doing wrong?

[Greg_Deckler]

Do you have any custom functions?

[Anonymous]

I do not...I guess this is the error. Can you tell me more about custom functions?

[v-lili6-msft · Accepted solution]

hi  @Anonymous 

This means that you haven't created a custom function in edit queries yet.

Just refer to these blogs:

https://radacad.com/custom-functions-made-easy-in-power-bi-desktop

https://hatfullofdata.blog/power-query-handwritten-function/

Regards,

Lin