Sorry I'm going to jump in the middle here. When you start up to laptop is it from sleep and cold start? And did I understand you have the issue when you plug it in?
If you haven't do these two things windows key + X select admin command prompt and run dism /online /cleanup-image /restorehealth
You said you had a lot of errors in event viewer so that will kill two birds with one stone. And not all events are errors that repeat.
next do a search with advanced options set to file contents in file explorer for you temp file address you can try with both c:\ and just the last part. I am wondering if something has added a command to open your temp file location inside an .ini or startup
file for a program.
The next thing I would try is closing the folder and turning off a process then enabling it to see if one pops up. I would guess maybe your DVD drive but that is just a guess.
EDIT
Sorry I was on my phone which had a mind of its own today
Look in here to see if there is a shortcut to the temp file location. It may be a hidden file so make sure in the file explorer ribbion the view tab has show hidden items selected
C:\Users(User-Name)\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup
While you are there you can look in all of them so see if there is a shortcut to it I would look in google to see if there is one since you said it happened more while that was in use. Maybe searching for the word "shortcut" or "temp" will
give you a list.