I can not change or create, the name of a directory with winrm in jenkins

hi,

I can not change or create, in a proper way the name of a directory with the winrm client plugin.
i use the follow code in the invoke-Comand

cd “C:\userdir\BKP”
set temp=%DATE:/=%
set dirname="%temp:~5,2%%temp:~7,2%%temp:~9,4%"
mkdir %dirname%

And this code create a folder named %dirname%
works fine like a .bat
thanks.