Help me with Win32:Trojan-gen. {Other}

[coolsocks]

OS: Windows XP / Avast Home ED.

O got this crap virus "Win32:Trojan-gen. {Other}" but he infected the following files:

-Rundll32.exe
-Rundll.exe

I got rundll32.exe from my windows XP CD. I cant find rundll.exe and
something is wrong: I cannot run avast, because my rundll.exe is
well.. what i can say... "cheated?"

I always get the message: "You cannot access the specified device, path or file,
you may not have the appropriate permissions to access this item"

PLease help!!... Thanks

[RejZoR]

Only Rundll32.exe should be located on your PC (located in C:\WINDOWS\SYSTEM32\ folder).
Rundll.exe and all other Rundll32.exe files placed anywhere else except in SYSTEM32 folder are malware.

[coolsocks]

Only Rundll32.exe should be located on your PC (located in C:\WINDOWS\SYSTEM32\ folder).
Rundll.exe and all other Rundll32.exe files placed anywhere else except in SYSTEM32 folder are malware.

Yeah but that virus infected the original files.. 
I dont know how to fix now.. cause some applications use
rundll to run (yeah, avast too)

[RejZoR]

Tell me where are your (infected) files located.
I need full path.

[coolsocks]

D:\Windows\System32\Rundll32.exe
D:\Windows\System32\Rundll.exe

[RejZoR]

Second one is certanly a malware.

Can you check both files with http://virusscan.jotti.org/ and post results for both here?
Thanks

[coolsocks]

Nothing wrong with the file and i've removed rundll.exe.
I think is a virus but i cannot run avast cause that error message,
i am only thinking in a way to remove this..

File:  rundll32.exe 
Status:  OK (Note: this file has been scanned before. Therefore, this file's scan results will not be stored in the database) 
Packers detected:  None
   
AntiVir  No viruses found (0.29 seconds taken)
Avast  No viruses found (3.01 seconds taken)
BitDefender  No viruses found (0.67 seconds taken)
ClamAV  No viruses found (0.79 seconds taken)
Dr.Web  No viruses found (1.20 seconds taken)
F-Prot Antivirus  No viruses found (0.12 seconds taken)
Kaspersky Anti-Virus  No viruses found (1.28 seconds taken)
mks_vir  No viruses found (0.48 seconds taken)
NOD32  No viruses found (1.65 seconds taken)
Norman Virus Control  No viruses found (1.91 seconds taken)

[RejZoR]

Well as you can see the file is clean. It must be a technical problem.
What kind of error do you exactly get when you try to run avast! (screenshot if possible)?