Hi, most, some still remain, of my local replays and scores have seemingly disappeared, I looked around forums which suggested using a backup of the scores.db file, however I do not have this file, any help would be great.
Have your beatmaps reprocessed recently or something?
In your file explorer, click on View > Hidden Items then go into your osu!\Data folder and check to see if you have a bunch of .osr files inside the "r" folder.
If you have files in that folder, you should be able to get them to appear in game again by renaming/removing your scores.db file (the actual one, not a backup). Make sure you do this while you have the game closed and I would recommend just renaming the file to something else instead of actually deleting it.