mepstool20u.dll is a mepstool
belonging to mepstool
from Watchtower Bible and Tract Society of New York, Inc.
Non-system processes like mepstool20u.dll originate from software you installed on your system. Since most applications store data in your system's registry, it is likely that your registry has suffered fragmentation and accumulated invalid entries which can affect your PC's performance. It is recommended that you check your registry to identify slowdown issues.