The Blank System Message command allows you to blank out an existing message in
a message file and rename the message ID. This is intended for bothersome
messages such as EDT0630 ('Have you tried the modern alternative to SEU?'). The
message will continue to be sent, but only blanks will appear on the display.
When BLKSYSMSG is used, a confirming display appears with the text of the
message to be blanked out.