Rundll32.exe create process

Today rundll32.exe wanted to execute MSO.DLL and than I’ve blocked it.I’ve never seen before. Is it normal? Second question when I started iexplore.exe,iexplore is trying to execute rundll32.exe.


MSO.dll is a part of Microsoft Office, so it should be safe. It should be safe for IE too. rundll32.exe loads DLL’s and places their libraries into memory. I guess IE needed/wanted to load a DLL, and therefore it starts rundll32.exe to do it.