title: github configure machine to use existing ssh key
body: <p>Background:</p>
  
  <p>I had a personal account that was working fine with github, then my employer gave me a new github account and so i configured my github account to use my machine generated SSH key. Now my old machine is replaced ....</p>
  
  <p>How do i configure this new machine to check-in check-out code to github..</p>
  
  <p>do i generate and add another key to the account?
  it is also asking me for email account..when i give my old(xxx@y.com) (email added on git hub) it says:</p>
  
  <pre><code>error: invalid key: xxx@y.com
  </code></pre>
  
  <p>Directly adding it says</p>
  
  <pre><code>*** Please tell me who you are.
  
  Run
  
   git config --global user.email "you@example.com"
   git config --global user.name "Your Name"
  
  to set your account's default identity.
  Omit --global to set the identity only in this repository.
  
  fatal: unable to auto-detect email address (got 'x y@DESKTOP-8ITRR8F.(no                                                                                                                                                                                               ne)')
  </code></pre>
  
  <p><strong>UPDATE</strong></p>
  
  <p>windows 10 doesnot allow creating a folder .ssh in c:/users/samra/..
  and when i try to generate key (thinking it may create a .ssh in the process) it says</p>
  
  <pre><code>Saving key failed: No such file or directory found
  </code></pre>