in reply to system() doesnt recognise director name with spaces

The shell requires that paths with spaces be quoted, just as when you type them at the keyboard. Use:

system( q["D:\\OKL\\Folder ABC\\uncompre" temp.gz] );

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.