shutdownsiebel.dll is a ShutdownSiebel
belonging to ShutdownSiebel Dynamic Link Library
from American Power Conversion
Non-system processes like shutdownsiebel.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.