title: Mercurial: "untracked file in working directory differs from file in requested revision"?
body: <p>Can anyone tell me what this Mercurial error means?</p>
  
  <blockquote>
    <p>untracked file in working directory
    differs from file in requested
    revision</p>
  </blockquote>
  
  <p>This occurred when doing an hg fetch: </p>
  
  <pre><code>C:\myapp&gt;hg fetch ssh://hg/myapp-v1
  pulling from ssh://hg/myapp-v1
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 93 changesets with 693 changes to 78 files (+1 heads)
  updating to 797:0df7dbe7dc06
  196 files updated, 0 files merged, 196 files removed, 0 files unresolved
  merging with 704:edb7765768c6
  abort: untracked file in working directory differs from file in requested revision: 'a/b/c/d.java'
  </code></pre>
  
  <p>From what I can tell this file (a/b/c/d.java) does not match any paths configured in .hgignore.  And this specific file is also identical in the two (myapp &amp; myapp-v1) repositories..   </p>
  
  <p>I am not clear what this even means.  ??</p>