When running an import rule with a csv data source using the data pre-processing function, the following error may be thrown:
Description: Failed to execute data pre-processing function. The pre-processing code threw an exception 'System.IndexOutOfRangeException: Cannot find column 0.
at System.Data.DataColumnCollection.get_Item(Int32 index)
at DataSourcePreProcessing.ProcessData(DataTable importData)
This issue is caused by using a data source that does not have column headers, and then adding the headers in dynamically using the data pre-processing function.
As a workaround, place the column headers in the data source, rather than using the data pre-processing function.
This issue has been adressed in KB 41359
Connector Solution 6.5