It aren't files in the registry, it are just lines with a label and number or text (in paragraphs in chapters if you like the analogy with a book).
And you can use regedit to add a new line with a new number or new text where-ever you like. So it seems you want to add a line labeled enabled with the value 1. Since your description of the problem and the solution is somewhat vague, I can't promise it will work.
I googled "windows startup file cannot be found" (with quotes) and your post here is the only hit, so it's a quite new problem. And for a new problem you might need a new solution. But it could well be there was another message than you say here, and you found the perfect solution.
After logging into my computer it appears with a black screen and an error saying that the windows startup file cannot be found. I've followed instructions on multiple other forums that all lead me to "regedit" through task manager, and the file Computer/HKEY_LOCALMACHINE\SOFTWARE\Microsoft\Windows Script Host\Settings.
All forums suggest that this folder should contain a file named "enabled" and that the data value should be changed to 1 instead of zero. The problem is that, on my computer the "enabled" file does not even exist. Is there any way to create or download this file again?

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