Coupon Discount not being subtracted Urgent Help Needed

i am new to oc and i have created a coupon enabled order totals enabled the coupon also. However on applying the coupon on view cart page it says "coupon applied successfully" but the total is the same as the item price. kindly help me solve this issue. i have installed some mods to enable coupon entry at the checkout page but all those mods didnt enable coupon entry at the checkout page i even tried vqmod but no avail. however in the middle of all this i messed my view cart page and now the coupon discount isnt being subtracted from the total. i thnk those mods spoiled the code. i have deleted all modifications and uninstalled all mods but still this thing isnt working kindly help.

my website url is www.fromkashmir.com the coupon code is '100' on all clothing items.

i am also attaching the screen shot..
i thought there is some calculation error or i have messed the code by installing free modules so i tried uplaoding the origional admin and catalog folder to my live site stil the error was not resolved .
all help apreciated..

well, you use two different common.js files, and they possibly try to do the same, but in a slightly
different way, who knows, and it's really just a wild guess. But at best, start again from scratch, by
use of default Source Files only.
Good Luck !
Ernie

i uploaded the origional files ( common.js) but still the discount isnt being subtracted..
kindly help me ...someone. i tried uploading all the php files but my site stopped working
can anyone suggest me which .php files effect the total amount in the view cart page so that i wil upload just those files to my server and c if the discount is applied?