"option casemap:all " doesn't work

[supercoollee]

i want to make my ASM case insensitive, but casemap:all doesn't work - assemble error.
why?

[hutch--]

Windows functions are ALL case sensitive.

[dedndave]

masm is also case sensitive by nature, with regard to data and branch labels
i never tried changing it, but i think you can - lol

[Slugsnack]

guess for names you can do 'equ's