Download Manager help

i'm using download manager to download big file like Zelda wind waker Iso, but it ask for password, then i checked the username and password required box, then insert My RomU ID and pass, but it still said password or username invalid
can anyone help?

if you are using firefox, use the plug-in called downthemall. it's a built in download manager for firefox.i've never used download manager, but i'm sure that there shouldn't be a username and password for it.