Can somebody please let me know if there is any configuration file for sound devices which affect microphone setting on the windows start up.

My problem is that when ever I start my pc all previously settings get over writen by some kind of default which mute my mic plus other iritating things which I have to change before I get functional Teamspeak2 ( a voice software for in game comunication). If you need anymore details fire away I will try to answer.

I have Sound Blaster Audigy in my pc.

AFAIK these settings are stored in the registry. But do you have any kind of software running capable of recording video or audio streams? I once tried a webradio application with a "recording button" and this did pretty much what you described, everytime I started it, the checkbox near "microphone" was unchecked.

yes I do nero has it own record utilities, I have sound forge, there is record tool from windows

I guess none of them will reset your mixer. Did this come all of a sudden?
I don't see similar questions on Google and Liveware /Creative Surroundmixer does not seem to have a specific issue like this. But Liveware / the Creative Surround Mixer is loading configuration presets on startup, one of them is temporary and stores what you did last and this may fail now. Unfortunately I don't have Liveware installed so I can't tell you how to do that exactly, but my idea is to write a preset patch with your settings, store it and see if this is being reset to nonsense on startup, too.
As much I remember, the opulent preset storing system of Liveware is entirely based on registry cramming (+4MB or alike) and maybe something went wrong there? One of the reasons I run my Soundblasters "drivers only".

I don't whant to advertise so if admin feel this shouldn't be here please delete it. There is a utility www.muvixer.com whitch I just installed on my pc and I will test it later but I been told it is actually working.
This utility will keep your setting even if some application will try to over write