I tried to install sitecore 9.1 but I got this error so unable to install, please help me
This error belongs to your windows user permissions. Just be sure that you run PowerShell as Administrator.
(When you call SetAccessRule() to set access rights on a windows file/directory, the user who will get the permission has to be a member of the Administrators group. If the user is not a member of the Administrators group PowerShell shows the error message Exception calling "SetAccessRule" with "1" argument(s): "Some or all identity references could not be translated.")