XML Parsing Error: undefined entity Location...!?!?!?

[mr.glynn]

for about the last week when using firefox and specifically when trying to download certain things from websites i get an error pop up that i've never seen before, it reads...

"XML Parsing Error: undefined entity
Location: chrome://mozapps/content/downloads/unknownContentType.xul
Line Number 30, Column 18: <description>&intro.label;</description>
-----------------^'

its realy annoying and is preventing me from using firefox as i should be able to, the things i am trying to download are things ive had no trouble with before and range from mp3s to jpegs and even dmg files. I really don't understand what the problem is or even what the message means, so if any one could help or knows what the problem is or what might be causing it or if its a problem with the latest release id be really grateful to know!

thanks.

[SK.]

http://kb.mozillazine.org/XML_parsing_error