David Carlisle almost certainly identified the problem: Do not use spaces in file names. Also avoid underscore, because it is a special character in TeX.
Sometimes you can deal with this by escaping the offending space (or underscore). But even when that works, it is something you are likely to forget, then the problem will re-appear and you won't remember why.
So, change the image file name to
Screenshot-1.png and also remember that the names are case-sensitive.
EDIT: This may also happen if there are spaces (or underscores) in the folder structure leading to the image. Also, if you use absolute paths on Windows, be sure that use use C://folder/subfolder rather than C:\folder\subfolder.
If you already have a folder structure and/or file names with spaces or underscores, and you do not wish to change the names, you can try escaping the characters like this:
folder\ name\ with\ spaces/folder\_name\_with\_underscores
Also see if that is done in your
If you do a lot of screenshots, perhaps you can change your operating system settings, so that the file name is saved without space or underscore.