Unable to install Xcode using dmg file downloaded from Apple.com I am trying to install Xcode 7.1 on OS X 10.10.5 using the dmg file downloaded from Apple. However, I have tried several times and the install always stopped at "Calculating size" when I dragged the icon to the Application folder. I waited for 2 hours and nothing happened. How can I install Xcode using the the dmg file?

My MacBook Air wireless adapter is damaged so I am unable to update Xcode from Mac App Store — the only way I can get Xcode is to download that dmg file.
Before doing this you need to delete the unfinished downloads and run this link in browser , which i mentioned below.
You can find the DMGs for Xcode and other development tools on https://developer.apple.com/download/more/ (requires Apple ID to login).
Link for Xcode 7.0.1 you can try this link.
Hope this will help.