Problem:
I have around 300 new items need to create in SAP business one 2005A. So I tried using Data Transfer Workbench to import the new object. However I get an error message as screen below. The business object that I choose is oItems.

The error message is "Item No. is missing [OITM.ItemCode] Application-defined or object-defined error65171".
I 'm using the CSV format for my import data files. The import template is get from the SAP DTW standard template. So I'm sure there is nothing wrong for the CSV file.
Sympton:
After I login to Data Workbench, at:
Step 1 - Business object, I choose oItems.
Step 2- Select data source file. I found that there are four items that i need to provide source file: Items, Item_Prices, Itemwarehosueinfo, itemcyclecount. However in DTW templates, i only found 3 example source file, there are no itemcyclecount.
Beside, I found that i have to provide a source file to "QueryParams", or else DTW will always show a message "A source file must be provided" and if not, I cannot proceed to next step.
Solution:
There are something wrong with the installation of the DTW. Re-install the DTW which is same patch with SAP B1.
Example:
SAP B1 2005a, patch 39, So the DTW must also the same patch version.
I had tried to reintall the DTW with the patch version same with SAP. I can fixed the problem and successfully import the new items into SAP Item master data.