Thank you so much for your response endecotp. I tried without certificates but got the same error. Here is how I tried but used cookies from google chrome instead of safari. Is there difference? wget https://download.developer.apple.com/Developer_Tools/Xcode_13.3.1/Xcode_13.3.1.xip --load-cookies=cookies.txt I created signing certificates that should have worked for logging to developer.apple.com - https://developer.apple.com/support/certificates

Thank you so much for your response endecotp. I think you are absolutely right about certificates and they cannot be used for authentication. I tried the way you told me but several headers like acn01, atsvric and dssid2 were missing from my cookies in browser. Eventually, I got the same error. I guess the way I am trying to automate the installation process is wrong and I need to download the required version of Xcode, have it saved on ftp server and then make all my machines to it and download. The downside of this approach is that Xcode itself is very heavy(about 9GB) so it will require several hours to download from another server to the target machines, which may not be the best way.