what is it?
ctrlpan.dll is associated with a trojan horse virus called Trojan.Bookmarker.B
What does it do?
This Trojan changes the Internet Explorer home page to
webcoolsearch.com. It is also packed with UPX. It is a variant of
trojan.bookmarker that modifies the Internet Explorer home page and
search page and adds bookmarks, which point to

pornographic Web sites; into the Favorites folder!.
When the Ctrlpan.dll file is loaded, it does the following:
- Creates the file hh.htt
- Adds the value:
"AppInit_DLLs"="ctrlpan.dll"
to the registry key:
HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersionWindows
so that each Windows-based program running......................
More info and Removal instructions
@symantec