You should do a DIC on Invoices. To do this:
1. Exit out of AR.
2. Open Invoices.
3. Select File - Check Data Integrity.
4. If the DIC found errors, you can click the Rebuild option to try to fix them, then repeat the DIC to ensure any errors were fixed.
NO ERRORS WERE FOUND.
If no errors are found in Invoices, then please answer the rest of my questions in the earlier posting. AMSWERS TO MY QUESTIONS ARE IN MY EARLIER POST (I AM NOT YELLING JUST TRYING TO DIFFERENTIATE MY ANSWERS FOR YOU :-)

Also, when you are referring to Account Codes, I am assuming you are speaking of the Customer Account Codes - ? Or are you referring to Ship To codes? Please be specific.
I AM REFERING TO GL ACCOUNT CODES

To find out which specification you are using for your CN's - go to the Open batch and click on the print button. You should now be at the 'Print batch of invoices' screen. Look at what specification is listed in the 'Credit note spec.' field. This is the description only - not the file name. You will now have to go into the Designer, and open each specification, then go to File - Specification Options to see if this is the correct spec. The name listed in the 'Title' is what you see when you actually go to print the documents. THANK YOU!