S&D not detecting anything...ever

[numbers]

Hi...I'm new so I hope that I've posted in the correct forum.
I have used S&D for a couple years on several other computers and it always detected something. I think this computer was already infected with something when I installed S&D - when I use S&D it NEVER detects anything - just gives me a "congradulations" message.
When I start S&D it starts to load then stops and starts over and finishes loading.
Could there be something on my computer that over rides S&D?

[tashi]

Hello.
Please go here and follow instructions.
Before you post a log

Start a topic here:
Malware Forum

Someone will then take a look at the system and advise you.

Cheers.