My list workflow on SharePoint 2010 foundation is created in SPDesigner. Sometimes it raises an error (from ULS log):
"Invalid data has been used to update the list item. The field you are trying to update may be read only." level Unexpected.
Periodicity is about 5% of all instances. How to get more info about this error ? WF History log cannot help me, because when WF crash there is only
"The workflow could not update the item, possibly because one or more columns for the item require a different type of information." in history.