Multiple instances of some process, should i worry?

[digam]

Hey,
When i go in details tab in the task manager, i see multiple instances of processes such as csrss.exe(6 of them) , dwm.exe(7 with username dwm-1, dwm-2, etc) , logonui.exe(4 of them) and winlogon.exe(4 of them).
Is there a problem with my computer.
I am using a local account and no other account is present. I have just used a live account to login in the store thats all.
I am a bit worried because it is not the same on my friend's pc.
thanks in advance

 

[johnbl]

-scan for malware.

open cmd.exe
cd c:\
dir /s dwm.exe

the file should be in your c:\windows\system32 directory
if it is in some other directory like
C:\Documents and Settings\yourusername\Local Settings\temp\dwm.exe
it is a Trojan

you should use a scanner to scan your system
here is a free scanner
http://www.malwarebytes.org/