1. You will need to have admin rights on the PC.
  2. First right click the plugin download link and use "save as" to make sure you get the file, and then run it yourself, that avoids the 'yellow bar' blocking issue.
  3. After installation of the plugin has completed go back to quakelive.com and if it always seems to think you have not installed the plugin then you must follow 4.onwards :
  4. Double click the bottom edge of the window where it says 'Protected zone'
  5. -> click the 'sites' button.
  6. untick the tickbox about server verification
  7. you need to add http://www.quakelive.com/ to trusted sites (NOT httpS)
  8. refresh or restart, whichever works.