A workflow crashes with a HTTP Status 400: Bad Request error, strange that it only happened on one list item. The workflow needs to copy an item in another site collection via a Nintex web service action.
As it turned out the reason is that the title contained an ampersand (&) character and the web service crashes on special characters. So we have to excluded the parsing of the title, this can be done with the term CDATA.
Add an build dynamic string action and wrap the Title around “<![CDATA[” and end with “]]>”.
Store the result in a variable and replace the title with the newly created variable.
Screenshot in Dutch.