I need help! ASAP

Relocate the files. Select one that is missing, select relocate, select all and let Rekordbox know that you want to relocate all missing files according to that location.

^^ That.

I can relocate one file, but I can't seem to relocate all files because they are in different maps and album folders. Is there a way so I can just order recordbox to browse my D:/ drive for the missing files or do I have to manualy go threw every album?

Did you move all of the files individually? Here's a couple of examples.

Scenario 1 - Original:

X:\Music\
       |
        ---- Artist1\
       |         |
       |          ---- Artist1-Track1.mp3
       |          ---- Artist1-Track2.mp3
       |          ---- Artist1-Track3.mp3
        ---- Artist2\
                 |
                  ---- Artist2-Track1.mp3
                  ---- Artist2-Track2.mp3
                  ---- Artist2-Track3.mp3

New location after move:

X:\OldMusic\

       |
        ---- Artist1\
       |         |
       |          ---- Track1.mp3
       |          ---- Track2.mp3
       |          ---- Track3.mp3
        ---- Artist2\
                 |
                  ---- Track1.mp3
                  ---- Track2.mp3
                  ---- Track3.mp3

The difference there is the parent folder changed from Music to OldMusic; this is a global move all within the same scope.

Scenario 2 - Original:

X:\Music\
       |
        ---- Artist1\
       |         |
       |          ---- Artist1-Track1.mp3
       |          ---- Artist1-Track2.mp3
       |          ---- Artist1-Track3.mp3
        ---- Artist2\
                 |
                  ---- Artist2-Track1.mp3
                  ---- Artist2-Track2.mp3
                  ---- Artist2-Track3.mp3

After files are moved:

X:\Music\
       |
        ---- First Tracks\
       |         |
       |          ---- Artist1-Track1.mp3
       |          ---- Artist2-Track1.mp3
        ---- Second Tracks\
       |         |
       |          ---- Artist1-Track2.mp3
       |          ---- Artist2-Track2.mp3
        ---- Don't Play\
                 |
                  ---- Artist1-Track3.mp3
                  ---- Artist2-Track3.mp3

In this situation, the containing folders of individual songs have changed - you can see that Artist1's tracks are no longer contained within the same folder, so relocating Track1 won't allow Track2 to be found within the same scope; it's moved by a different value, and using a mass-relocate won't work.

So the question is this... what did you do to move your files around that requires so much effort in relocating them?

Thanks for your reply. The scenario I have is:

C:/.........music (gone)

So now I have

D:/.......music

It's only the drive that changes, nothing else. Is there a way I can let rekorbox know the music is no longer in C..... but in D....

I have around 8000 tracks in 500+ different folders, so manualy doing it would be a pain to say the least. Ofcource I can do that, but is there a faster way to do it?

Thanks in advance

Yes! Select ALL songs in your collection (CTRL + A), then find one file which is missing, right-click on it, select "Relocate" - you'll be prompted to locate ONE missing file (not necessarily that file you clicked on), and when you do find it, and click OPEN, it will ask if you want to use that same location to relocate all other missing files - click YES and rekordbox will start to identify the existing files based on the change of the first file.

If the only difference is a change from C:\ to D:\ but the remainder of the file path is the same, they'll all be located in a matter of seconds.