yahoo.sharedwpf.dll is a DLL file that is part of the Yahoo.SharedWPF program. Yahoo has a multitude of applications, and this file is a part of one of those applications. If you have noticed this file on your computer at start up or after a crash and re-star, then you most likely have an error related to this file. It is highly recommended that you have your computer scanned to discover what the nature of the error is.
ZookaWare PC Cleaner is an excellent registry cleaner and can clean up and clear errors usually on the first scan. ZookaWare PC Cleaner offers a diagnostic scan that will be able to tell you what type of error it is and if you should invest further into ZookaWare PC Cleaner. ZookaWare PC Cleaner is also a member of the Better Business Bureau, so you can feel confident that the reading you get is accurate and fair.