External drive not detected by computer

ok forgot to check the "more lost files (raw)" folder.

Now just recovered the avi wmv flv mpg mp4 mkv sub folders from more lost files raw folder and it's 1.45 TB. About 75% are full sized and full and the rest are corrupted? Showing exact full size files but couldn't play them.

So I found a lot more videos that I couldn't find. Raw folder means they don't have the file name just file00001 file 00002 etc. This more lost files raw folder is only accessible by the deep scan method.

So probably 75% of 1.45 TB = 1.1 TB + 150 GB = 1.25 TB out of about 1.77 TB are found and work properly. The rest either have full sized files but corrupted (not playing on media players) and 0 kB.

If the corrupted files (the ones with full file size) are playing, the number of TB I found would be higher.

Anyway to fix full sized files that are not playing?

And by the way I am backing up data daily and have 2 antivirus software working together. One of them is Kaspersky. To prevent virus attacks that can wipe off all data and operating system.

is it normal that people can't get 100% of files back.
I got only about 70% back. The rest are just 0 kB and full size but damaged.