Masm indirect addressing mode for MOV commmand

Question

I've tried the following forms and masm doesnt like any of them:

mov byte [myVariable], al
mov byte ptr [myVariable], al
mov [byte myVariable], al

what am i missing? why cant i seem to use indirect addressing.

the error i get from masm is 'Missing operator in expression" on some of the lines, some of them say "Structure field expected"

Answer 1

mov [myVariable], al

should be sufficient, or even just:

mov myVariable, al

But then again mov byte ptr [myVariable], al should also work, which makes me wonder "what is 'myVariable'"?