title: "sorry, we can't load add-in" Office Word add-in
body: <p>On MacOS, I'm developing an Office Word add-in. All has been going well until this morning when I woke up myself and my laptop, fired up the add-in (npm start), and clicked on the add-in in the ribbon at which point I got the message:</p>
  <p>&quot;sorry, we can't load add-in. Please make sure that you have network and/or Internet connectivity . . .&quot;</p>
  <p>This occurs not only with the add-in I'm developing but also with the test add-in that comes with yeoman.</p>
  <p>Things I've tried (on both my add-in and the Yeoman-supplied one):</p>
  <ol>
  <li>npm run dev-server – compiles successfully, reporting &quot;Project is
  running at https://localhost:3000/&quot;</li>
  <li>reboot of computer</li>
  <li>netstat -vanp tcp | grep 3000 – reports nothing.</li>
  <li>restart my XAMPP server</li>
  <li>npm run validate – successul validation of manifest.xml</li>
  <li>https://localhost – produces the dashboard of XAMPP</li>
  <li>https://localhost:3000 – produces 'Unable to connect' although at one point I did get a listing of files and their icons in the add-in (but still the error message in Word).</li>
  <li>npm start – (several times including shutting down Word beforehand).</li>
  </ol>
  <p>EDIT: I have, just after posting the above, noticed that if I do the following:</p>
  <ol>
  <li><p>'npm run dev-server' (while Word is running and the add-in is in the ribbon), the add-in will load correctly and function. https://localhost:3000 in the web browser now displays the files and icons.</p>
  </li>
  <li><p>If I follow 'npm run dev-server' with 'npm start' (while Word is running and the add-in has been loaded from 1. above), I can continue to use the add-in. If I close the add-in and attempt to open it again, I get the error message.</p>
  </li>
  <li><p>If I close Word and run 'npm run dev-server' then 'npm start', I get the error message when clicking on the add-in the ribbon.</p>
  </li>
  <li><p>Running 'npm run dev-server' and trying https://localhost:3000 in the web browser works, then 'npm start' and https://localhost:3000 no longer connects.</p>
  </li>
  </ol>
  <p>'npm start' reports:
  office-addin-taskpane-js@0.0.1
  start office-addin-debugging
  start manifest.xml
  Debugging is being started...
  App type: desktop
  Sideloading the Office Add-in...
  Debugging started.</p>
  <p>For the past few weeks, from the terminal I have been just running 'npm start' with no problems until this morning. It appears that 'npm start' is suddenly shutting down its own server.</p>
  <p>All help and advice gratefully received.</p>