W2C Combined MMREF-2 file

We were in 4.6C for the 2007 year end. When W2Cs were run, they did not create the mag media files when they ran the production W2Cs. We upgraded to ECC6 in 2009. We now want to create MMREF-2 files for the 2007 W2Cs. I have tried selecting the Generate magnetic tape and Combine MMREF-2 buttons on the W2C screen, putting the last as-of-date for the 2007 W2C production runs, and choosing Print Copies. From what I found in SAP notes, this is what we should do to combine all the runs into one file. But - I only get a few of the W2Cs generated into the file. Any ideas on what I need to do to get all the W2Cs into the MMREF-2 file?