winpack.exe is a process belonging to Troj/Dloader-JU Trojan.
When executed the process will try to download and execute new files from an online server. This process should not be removed to ensure that your system is secure.
Non-system processes like winpack.exe 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