SML's &SETKEY command does not allow any function key to be set. Another common problem is that &SETKEY does not work if used in a compiled SML.
ANSI.SYS is either not present in the CONFIG.SYS file, or it is not getting
Make sure that the following line or its equivalent is present in the CONFIG.SYS file:
&system "&setkey f1 commands &cr
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