title: Why does .MSI file open read-only?
body: <p>I am attempting to open a <strong>.MSI installer package file</strong> to modify it. Whenever I try to open it, it opens in <strong>read-only mode</strong>. I see this with <a href="http://msdn.microsoft.com/en-us/library/aa370557%28v=vs.85%29.aspx" rel="nofollow">Orca</a>, with <a href="http://www.instedit.com/" rel="nofollow">InstEd</a>, or when opening the file directly via code:</p>
  
  <pre><code> `MsiOpenDatabase()` (ERROR_OPEN_FAILED with MSIDBOPEN_DIRECT or 
                        MSIDBOPEN_TRANSACT persistence modes).
  </code></pre>
  
  <ul>
  <li>The file itself does <em>not</em> have the read-only attribute set (in fact, has <em>no</em> attributes set)</li>
  <li>I am using an account with Administrators group access</li>
  <li>As far as I can tell, no other process has the file open</li>
  <li>No installs are in progress or suspended</li>
  <li>I can copy the file to another location, and open it read/write there. But the original, I cannot touch</li>
  </ul>
  
  <p>Thanks in advance for your help.</p>