Basic hashcat mask syntax

[WhalerTom]

The mask you specify is not ?1?1?1?1?1?1?1?1 as you could think, it's just "?1". That's because of the --increment option. If you remove it the warning will be be gone.

Thanks for your answer, but if I run with "?1" instead of "?1?1?1?1?1?1?1?1" it shows the same warning then stops after trying 1 combination as if I were specifying a 1 character long password.