l1ttut.dll is a DLL file of unknown origin. DLL files can contain code, data and/or resources and can be accessed by multiple programs. It could be a benign file left over from the improper installation or deletion of a program that is simply getting in the way of your computer by doing what it should be doing, or it could be a security threat.
Either way, it is important that your next step is to clean your computers registry. ZookaWare PC Cleaner will do a free check of your computer and tell you about all of the errors that are slowing down your computer and potentially causing it to crash or worse.