This problem has been plagueing me for very long, and i cant find if its a software setting doing it, or the fact that my hardware is shot up, or not meant to do as i want anyway lol!

I own a Dimension 8300 with Windows XP and a SoundBlaster 5.1 Live Digital soundcard, and i am attempting to get working (one of my TWO) microphones. I have been plugging these microphones (and they both work fine for sure on other peoples computers!) into the red microphone jack on the back (which for some reason was covered up with a hard to remove cover when i got the Dimension, is this normal or does that mean that these plugs are inoperative...MAYBE THATS WHY I CANT GET THIS TO WORK!) and the computer refuses to allow me to speak through them, even after fiddling with Creative's programs, changing the plug to the line-in and using that, makng the microphone unmute from the volume bar eg, nothing works! I have purchased Dragon Naturally Speaking Standard and seriously, im in deep trouble if i cant get a microphone working (unless i spend more non-existing money on a USB microphone...would that solve my problem?!) as its just an expensive LUMP without a microphone obviously. One of these two microphones is a headset style, the other is a desktop style, and they both wont work at all! Not even a whimper goes through, with microphone boost on or not, and im starting to believe that the red jack is totally dead or never worked in the first place. But come on, this aint the cheapest soundcard out there, as if i dont have microphone functionality!? What could be causing this?

Does anyone have any good ideas here? Ive probably already tried everything there is, and am maybe here just for confirmation so i dont feel as guilty saving up for a USB microphone. But if anyone can save me the money id much prefer it, and ANY hints or tips would be deeeply desireable! Thankyou!!!