title: How to create xpi file with 7Zip?
body: <p>I would like to pack my firefox extension as xpi file. I tried by adding it to archive and name it as filename.xpi </p>
  
  <p>But when i try to install it on firefox am getting "package corrupted" message. Is there any way i can create a valid xpi file ?</p>
  
  <p>I have installed cygwin and tried to execute zip command to create xpi file. But got zip is not a command error. </p>
  
  <p>Can somebody guide me to get it done ?</p>