To import Purchase Orders to MYOB you must first setup a purchase account “5-XXXXX” and the Supplier must exist in MYOB (case sensitive). The Card Type must also be set to Supplier, otherwise MYOB will not accept the import. 
To Export Purchase orders to MYOB (Offline Version via a csv file), head to Purchase Orders => Ready to Export.
These are Purchase orders stamped ready to be exported.
Click on Export MYOB CSV to download the text file
Open MYOB and select File => Import/Export Assistant
Then choose the following settings when completing the import
Select “Purchases” & “Service Purchases”
Select the following:
Select “Match ALL”
Then Click Import
Check the log file after the import for any warnings or errors
Errors identify that the record was rejected (did not import).
Warnings advise that the record was imported however it may not be as expected.
