Purge POBS 4.2

Since version 7, Primavera P6 takes a lot of time to import XER files. This is due to a programming error, which causes POBS data being transferred via XER files; every import POBS information adds to the information already in the database. Purge POBS removes the unwanted POBS table data out of the XER file and prevent further additions to the database, thereby reducing the import times.