Add robots.txt file to the root directory using PowerShell
$fileBytes = [system.io.file]::ReadAllBytes("c:\the\full\path\to\your\robots.txt"); $site = Get-SPSite "http://yourdomain:portifneeded"; $site.RootWeb.Files.Add("robots.txt", $fileBytes, $true); copied from: http://www.jonthenerd.com/2011/08/17/sharepoint-2010-add-a-file-to-the-root-of-your-site-using-powershell/