sp.dll is a process belonging to the Adware program . sp.dll is an Adware related DLL which changes your homepage to one specified by the Adware's author.
Check that sp.dll is stable on your computer.

DISABLE AND REMOVE sp.dll IMMEDIATELY. This process is most likely an adware or spyware. It is highly recommended to run a FREE performance scan to automatically optimize memory, CPU and Internet settings.

Determining whether sp.dll is a virus or a legitimate Windows DLL depends on the directory location it executes or runs from. Click to Scan your PC including sp.dll to Detect any Security Threat.