unable to chmod inside shared folder of virtualbox

I have shared a folder from Windows on to my virtual machine. The shared folder is being mounted correctly, and I am able to read write within the folder, but unable to change permissions of any file within the shared folder. Below are the mount options of the shared folder myVM on /media/sf_myVM type vboxsf (rw,nodev,relatime,ttl=0,iocharset=utf8,uid=0,gid=999,dmode=0770,fmode=0770,tag=VBoxAutomounter) user is already part of vboxsf group uid=1000(vmuser) gid=1000(vmuser) groups=1000(vmuser),4(adm),24(cdrom),27(sudo),30(dip),46(plugdev),116(lpadmin),126(sambashare),999(vboxsf),1001(sftp) Below error is thrown when try to change permissions using chmod for any files inside shared folder. chmod: changing permissions of 'perm.txt': Operation not permitted