Soda-88 :
^
You're confusing svchost with dllhost, they're not the same.
Size of Windows 7 64bit version dllhost.exe located in \Windows\System32 folder is 9.728 bytes
Size of 32bit version located in \Windows\SysWOW64 (or \Windows\System32 if you're using 32bit Windows) folder is 7.168 bytes
If you've got a different value then do as zhihao50 said and reinstall Windows.
The file svchost on my computer is of 27kB size and dllhost is 9.5kB. I'm using Windows security essentials antivirus, it haven't detected any virus.
Moreover my main problem is my windows photo viewer crashes frequently, while browsing 10-15 photos in photo viewer with right arrow key it crashes and shows me error below. Do you think it is because of size of svchost or virus, I have tried almost all the methods in the internet to find the solution but has been unsuccessful. Plz help..
COM Surrogate has stopped working
Problem Event Name: APPCRASH
Application Name: DllHost.exe
Application Version: 6.1.7600.16385
Application Timestamp: 4a5bca54
Fault Module Name: igdumd64.dll
Fault Module Version: 8.15.10.2653
Fault Module Timestamp: 4f3aac44
Exception Code: c0000005
Exception Offset: 000000000030eb06
OS Version: 6.1.7601.2.1.0.256.1
Locale ID: 16393
Additional Information 1: 4821
Additional Information 2: 4821355ca40f333f44457bc45edd13e4
Additional Information 3: 8679
Additional Information 4: 86792858eda0533051313d5b6c961a51