You may use Norton Antivirus and notice long startups as it churns thru scanning the startup files.

Or perhaps you don't even use it for that very reason.

To avoid this, simply place the Norton Antivirus AutoProtect extension in the System Folder...move it there from extensions and restart. Now, it will load LAST and your startups will be fast again. It still provides ALL the protection, it just loads last in the startup sequence and doesn't scan those startup files every time you start.