Panasonic PanaVOICE system Technician Manual page 72

Technician's Guide
Installing PanaVOICE with an OAIIntegmtion Z-67
Note
Each time you run Mailbox Builder, the new Mailbox Builder Report
(BOXBUILD.LOG) overwrites the previous BOXBUILDLOG report. If you
want to save a Mailbox Builder Report, you must copy the report using
a different name before running Mailbox Builder again.