Data Format Error - Couldn't convert to number / Details: To be removed

[Anonymous]

Hi all,

I am working with a large dataset, combining different sources of excel files. For some reason, from one moment to another, I get an error message stating "Data Format Error - We couldnt convert to number. Details: To be removed". 

It occurs at a step where I try to expand a table after merging a query. Even if I delete all following steps and try to re-do everything it gives me the same error message. I have no idea what I did wrong/different that this suddenly appears...

Does anyone know how to resolve this issue??? It's extremely frustrating 😕

[Stachu]

does the Excle file that you expand have any errors like #N/A or #VALUE?

[Anonymous]

@Stachu : I am expanding the file using a match of a unique ID and trying to expand three columns (out of 16). The 3 columns I want to add all include text (also signs like e.g. "-"). In the other 13 columns, there are all sorts of symbols / signs such as e.g. Chinese symbols). 

However, the entire document is an external & hard-copied report, so there are no error-messages as such. 

Is there any way I can avoid that Power Query is attempting to automatically convert specific columns to number format?

Thanks for your time.