When considering a purchase for a desktop alert type mass notification system avoid a system (or designing a system) that employs the usage of a browser pop-up window as the alert agent.



REASONS
  1. End User Key Macros will close the window (Alt-F4 etc)
  2. The user can minimize the alert
  3. Browser Pop-Up blockers will block alert
  4. Window can lose UPPERMOST window status by something as simple as a mouse click on a document and the user will not see the alert
  5. The pop-up is reliant on scripting which opens a myriad of issues all which may result in the pop-up window not opening at all.
  6. Browsers crash
There are many other reasons.  This is a highly ineffective and unreliable method.