First things first;
Ewido is now part of AVG and has been for some time now,so i think you need some updating.
Secondly ,i believe PC Guard to be an antivirus program,now assuming you have AVG free antivirus installed.....you will have problems as two AV's will conflict.
You have a Smitfraud infection and may need specialist help.
Ok,if you have two AV's installed-remove one via add and remove programs.
Download and update Mbam click here then boot into safemode and run.
If this fails to remove this Smitfraud infection you are going to need help.
Read this first click here
and post the log click here