The DSX system software Instructions menu mailbox numbers changed during the life of the system.

The Legacy system version 2. were Instructions mailboxes 001-008.
Version 3.0 Instruction mailboxes are 801-808.

Version 3. era had major software changes. You also had upgrades to Admin software as well.
Extension numbers changed. Example: 300 up one 301. 301 became extension 302, etc.

So you need to determine what software is currently used.


-TJ-