I'm generating a reference number in a custom list in sharepoint designer. The process then waits for that to be set and copies the reference number across to a new entry in a tasks list.


The reference number in the custom list is of type 'single line of text' and is the title column in the list. In the tasks list the field is a lookup field but fails to take the reference across and gives:

Coercion Failed: Unable to transform the input lookup data into the requested type.

Has anyone had any experience with this issue on workflow

  • Are you copy/pasting the lookup field to another area?
    – MickB
    Commented Dec 9, 2014 at 14:39

2 Answers 2


I am very new to SharePoint so I am not conversant with its jargon. Being someone that comes from a relational database background, am going to explain this best way I can and hope it helps out.

So in my case, the conflict is as a result of a data type miss match. The lookup column in the library expects a value of data type integer while I was of input a string value hence the 'Coercion Failed: Unable to transform the input lookup data into the requested type.' error.

I discovered that the lookup column in my library did not use my 'primary key' to make reference to the other list where I needed to get my values from.

DocID is what I am using as a primary key in my library

Instead what is used as a reference column is a system generated column named ID and is of type integer. Simply changing the field from source to ID fixed my problem.

Change field from source to ID


works when the field is set to ID instead

  • could you elaborate on this? Commented Jun 22, 2020 at 15:39

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.