I have never used the function for scanning negatives, a friend asked me to scan some negatives for him, on my scanner there is a black plastic sheet with a hole in it for transparencies, I laid the neg on this as it said horizontal and scanned it, I just got a bad scan of the negative. The help section does not cover this part of scanning and their site gives error messages for any help.
Does anybody know how to do this or have this scanner ??

From their step-by-step manual:

Properly position your photo, filmstrip or slide on the scanner bed.
To scan transparent materials, you should install the Transparent Media Adapter before positioning your material and launching ScanWizard 5 (Refer to other documentation on installing the appropriate accessory).

To activate ScanWizard 5, click the icon on your desktop.

If you are scanning a film or slide, click Original Original, then select from the menu Positive (for slides) or Negative (for negative film from cameras).

Here's a link if you don't have the manual handy:
ftp://ftp.microtek.com/microtek/support_pdf/PC_tu_SW5_0802.pdf

I did finally figure out that i had not changed to film negative part so i did get it to work but thank you for the additional help.