Generating Source Lists

Hello,

I am generating source lists for OA's using the mass update tool. For some OA's rather than receiving the "Following records will be deleted: ... Following records will be created: ..." message it is showing only "Following records will be deleted:" I would appreciate it if someone could explain why SAP is not going ahead and generating a source list, and tell me what I need to do to correct it so that one will be generated.

Regards,

Judi