Set "everyone" Permission to Folder using C# in Asp.Net

string redirectionFolder = @"D:\test\subtest\";

FileSystemAccessRule everyOne = new FileSystemAccessRule("Everyone", FileSystemRights.FullControl,AccessControlType.Allow);
DirectorySecurity dirSecurity = new DirectorySecurity(redirectionFolder, AccessControlSections.Group);
dirSecurity.AddAccessRule(everyOne);
Directory.SetAccessControl(redirectionFolder, dirSecurity);


Note:
If you get the error "Attempted to perform an unauthorized operation"

add the tag (<identity impersonate="true"/>) in your web.config file.