Flash
From MozillaZine Knowledge Base
Make sure you used the installer, and not the zip version.
Download flash here: http://download.macromedia.com/pub/shockwave/flash/english/win95nt/7.0.14.0/flashplayer7installer.exe
If you have troubles, try installing an older version from within firebird: ftp://ftp.netscape.com/pub/netscape7/english/7.1/windows/win32/jgksyc//flash.xpi
For more information, visit plugindoc: http://plugindoc.mozdev.org/faqs/phoenixwin.html