GitでClone via sshしようとしてエラーがでたとき

こんなエラーがでたときの対処方法

[e-mail]: Permission denied (publickey).
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.

1. Open git bash (Use the Windows search. To find it, type "git bash") or the Mac Terminal. Pro Tip: You can use any *nix based command prompt (but not the default Windows Command Prompt!)
2. Type cd ~/.ssh. This will take you to the root directory for Git (Likely C:\Users\[YOUR-USER-NAME]\.ssh\ on Windows)
3. Within the .ssh folder, there should be these two files: id_rsa and id_rsa.pub. These are the files that tell your computer how to communicate with GitHub, BitBucket, or any other Git based service. Type ls to see a directory listing. If those two files don't show up, proceed to the next step. NOTE: Your SSH keys must be named id_rsa and id_rsa.pub in order for Git, GitHub, and BitBucket to recognize them by default.
4. To create the SSH keys, type ssh-keygen -t rsa -C "[e-mail]". This will create both id_rsa and id_rsa.pub files.
5. Now, go and open id_rsa.pub in your favorite text editor (you can do this via Windows Explorer or the OSX Finder if you like, tpying open . will open the folder).
6. Copy the contents--exactly as it appears, with no extra spaces or lines--of id_rsa.pub and paste it into GitHub and/or BitBucket under the Account Settings > SSH Keys. NOTE: I like to give the SSH key a descriptive name, usually with the name of the workstation I'm on along with the date.
7. Now that you've added your public key to Github and/or BitBucket, try to git push again and see if it works. It should!

More help available from GitHub on creating SSH Keys and BitBucket Help.

引用：https://gist.github.com/adamjohnson/5682757#file-publickey-git-error-markdown