Internet explorer not updating
Would you like to answer one of these unanswered questions instead?In order to speed up web browsing, web browsers are designed to download web pages and store them locally on your computer's hard drive in an area called "cache".I know this is a really old question but it is also one that is still relevant, though these days applies only to mozilla.(I have no idea what explorer does coz we don't code for non standard browsers).Browser cache (also know as Internet cache) contains records of every item you have viewed or downloaded while Internet surfing.
If your plugins provide a favicon (which - illogically - many do), they might override the one you desired to use - given yours is in a plugin itself.
It seems pretty silly to always cache them given they are normally only 16x16.