Solution : https://service.sap.com/sap/support/notes/502736 (SAP Service marketplace login required)
Summary :
When using Transaction MIR4 to modify a parked invoice, changing the posting date to a different fiscal year or altering the document type in the 'Detail' tab (which also changes its number range), will assign a new document number. Upon revisiting this document, issues arise: the purchase order reference field appears empty, and the purchase order structure is missing. This is due to a program error. The resolution is implemented in SAP Release 4.7 or via a Support Package for Release 4.6C, with detailed correction instructions provided in an attachment.
Key words :
purchase order reference reason, purchase order reference, purchase order structure, 'detail' tab title, advance correction instruction, parked invoice document, document type, document number, transaction mir4, posting date
Related Notes :
494473 | Change fiscal year/doc type for externl IR number assignment |
366965 | MIR4: Changing posting date of parked documents |