Why not try a reinstall ? Been quite some time I tried Spybot Search and Destory. It was very famed once, tried in those days. How is it now ?
A google search revealed that the most probable cause may be due to the incompatibility with Win 8(unless you are using KS version 2013).fixed the issue ... it was because of the SDupdatye service was not starting properly but after sometime it stared up properly and update the necessary componenets though have to run this for 3 times but the most funny part is the log file is not showing any such things ... SD needs to improve it's win 8 compatibility.
Now facing one more issue with KS Virus Removal Tool .. the damn thing is throwing up client Registry Error and asking me to reboot into safe mode. It would have been better if it can be used without rebooting windows .. I'm using win 8 x64 version.
a good AV is always recommended unless you have great trust in your pc skills & technical knowledge(& by that i don't mean the usual but the deep level windows system working,group policies,restrictions,virtualization etc).you can use avast v8 free or avira free.for firewall you can try windows 7 firewall control which basically gives a nice user interface to existing windows firewall.btw if you are behind a modem/router(which most home users are) then you can use the modem/router hardware firewall which is better than any software firewall.
As already told by whitestar, it is automatic in case of PPPOE connection.Do I need to setup the router firewall myself or is it automatic? I am using a router given by BSNL for broadband connection. And I don't have the password for the router.
Some points -I want to be careful too.
But don't know exactly how.
I need a guide line.
Using Avast Free at present.
the most dangerous way to get infected is by so called "drive-by downloads".in this method you just have to visit an infected website which may be a reputable/known site & not shady(bbc radio site was infected in a previous year) & without clicking anything your pc will be infected.this method relies upon windows system vulnerabilities(always install windows security updates as soon as released usually around 12th of every month),java vulnerabilities(unless absolutely needed uninstall java else always run latest java update),flash vulnerabilities(always use latest flash player version),browser vulnerabilities(always use latest browser version) & many of these vulnerabilities also depend on running scripts in web pages so i recommend using firefox with noscript addon with default whitelist config in which i only temporarily allow some scripts to run on a particular website(like those filesharing sites which need captcha to enter,video streaming sites etc).it is a hassle though but after using firefox with noscript for so long i can easily handle it but for newcomers it will be difficult to follow for some time.
I must say avast has done a great work on UI as far as ver 8 is considered. I really wish some attention was paid towards the protection level. I'm saying this because of an incident occurred few days ago. A friend of mine had requested me to install antivirus in this PC. His system was infected heavily. When I installed Avast 8, as one would expect viruses would be caught active in memory, but to my surprise, NO. I ignored it and started scanning. The point to notice is that, I had inserted a pen drive, and virus, which was active in memory was continuously replicating itself in the PD; and shockingly, Avast detected all the viruses in the PD in real time, while virus was replicating it, in parallel. Avast should have detected and cleaned the virus active in memory in first place, but I guess it was too busy in increasing the count of viruses it caught. I was in total dismay. Thy shall not be forgiven.
Bbye Avast. (only if I would have tried thou)
even webshield & WOT won't protect you if you are visiting a legit/reputable website(like bbc radio) designed to exploit java/flash/windows vulnerabilities.this is how facebook,twitter & new york times got hacked.this is also why in cyber black market such zero-day java exploits sells for $10000 a piece.
If a computer is infected heavily then the best thing you can do is Boot time scan which will cure the system in most cases. When a file is replicating itself then it is basically in use so windows don't allow it to be deleted, that could be the problem.
@dashing.sujay,maybe there is some new optimize scan setting in avast 8 which skips scanning memory to minimize ram usage by default.this may explain why avast caught created files but missed the running culprit process.
edit:it seems like when using custom scan option you have to select "memory scan" option to enable scanning of memory.this option seems to be disabled by default.i don't use avast 8 but you can try looking into settings to see where exactly is this option.