'Msconfig' does not show all the starup entries though.
It actually shows extremely little.
(especially when malware is involved... not saying the above problem comes from malware though, but there is always that chance).
On top of top, if you change something in msconfig, an alternative bootup sequence is created. In other words, the entry is never really removed.
You better use
AutoRuns for stuff like that, even for common problems or small changes (because of the not-really-removing issue).
But even if msconfig would show the process involved in this message, it does not necessarily show that filename ("fiveslowslow.6rlaa") and thus you still would not know where it comes from.
On the other hand, you could simply search for the file via Start > Search > Search for files...
But make sure you also tick the advanced options:
- Search also in system maps
- Search hidden files and maps
- Search submaps
If the file is found, it would give you the folder where it is located. And that folder name might give you a big clue as to what program tries to run it.