Sorry to say that you have a virus, but its not all lost, here is the answer :-
SYMPTOMS
When you start your computer, you may receive an error message similar to:
Registry Editor: Cannot import C
Windows\Kak.reg: Error opening the file. There may be a disk or file system error.
In addition to or instead of the error message, you may see a blank box with the following title:
C
Windows\Start Menu\Programs\Startup\Kak.hta
CAUSE
This behavior is caused by the Wscript/Kak.worm virus, which uses ActiveX and Windows Scripting Host to spread by using Microsoft Outlook Express 5.
RESOLUTION
There are two methods to remove this virus.
Method 1
Obtain and install an antivirus program that can detect and remove the virus.
Method 2
Manually remove the virus:
Quit Outlook Express.
Install the Microsoft scriptlet.typelib/Eyedog security update. Information about this update is available at the following Microsoft Web site:
ftp://ftp.microsoft.com/peropsys/IE/IE-Public/Fixes/usa/Eyedog-fix/x86/q240308.exe
Search for all files named Kak.hta and Kak.htm and delete them.
Delete the default e-mail message signature in Outlook Express. To do this, start Outlook Express, and then click Options on the Tools menu. Click the Signatures tab, click the default signature, and then click Remove to delete it.
Delete any messages that may contain the embedded script.