Today, I was trying to update a list item with some data using the Update listitem action in Nintex and I got

Coercion failed: Unable to transform the input lookup into the requested type

The string value that I had was “Other;” and I tried to update a lookup field with this string. Once I removed the semicolon the problem went away

Coercion Error

The annoying pain in this case was that the workflow even though it had started there was no ‘In progress’ or ‘Failed’ link to the workflow history.

Also, during my debugging I disabled the update item action, but the disabled action still caused the workflow to fail in the same way.