Everything is out of place like the files are hidden

Open command promt and type these: (put your drive letter in place of X )
X: (enter)

attrib -r -s -h *.* /s /d (enter)
all the files in that drive will be visible now..
Source:
http://tech-soln.blogspot.com/2013/02/how-to-recover-hidden-files-from.html

Click start control panel,folder options select view scroll down to hidden files and folders tick in show hidden files and folders
or in the folder options place a tick in the single click to open circlce/box
hope this helps

The other folders may be hidden.
To show hidden folders and files.
Open the drive - Click on Tools - Folder Options - View tab and enable Show hidden files and folders.

Had the same problem. I did a little digging in the file structure on the player. There are a couple of hidden folders, one of which is called ".trashes". When you delete a file on the disc is just places it into this hidden folder. It never actually takes it off the player. I used the Disk Utility app in OS X to format the drive, which cleared out the unwanted files. All the hidden folders stayed in place. Then I had to re-create the "Kids Mp3 Boombox" folder and put in the songs I wanted. Everything seems to be working fine now, but I imagine I will have to repeat this process any time I want to remove a song. Its probably a lot easier to just buy an SD card and use that!

control panel,folder options select view scroll down to hidden files and folders tick in show hidden files and folders
or in the folder options place a tick in the single click to open circlce/box
hope this helps

Try turning on the "show SYSTEM files" option in the folder views. Right inderneath the show hidden files.
Also, you might be looking in the wrong places. It sounds like a virus or part of one. Could be hidden almsot anywhere. Could even be created by another process on bootup so the file is really only a "virual" file.

Avast is Free and is a GREAT antivirus utility

Download and run CCleaner. It's a free program that will clean up all temp files and more without damaging your system.

IINSTALL ANTIVIRUS

It may have created a hidden system file.
Open explorer and then right click on each of the main folders on the left side. If you see a folder that is absolouty huge, then that would be a good place to start looking.

You will need to unhide hidden and system files as well.
This will depend on your OS so ..
For Vista:

1. Open Explorer
2. At the top of the page select Organise
3. Select Folder & Search Options
4. Select View
5. In the Hidden & Search options, tick "Show hidden files and folders"
6. Hit Apply, then up the top "Apply to all Folders"

For XP

1. Open Explorer
2. Select Tools /Folder Options/ View
3. Then it's the same process as above.

Hope that helps.

you can fix the problem by having the original sansa files when you format it it deletes everything
get a friends sansa files or do this
and just because it would be a pain looking for the original files i uploaded here for people who deleted them put these files into a folder named

DATA http://www.divshare.com/download/4002990-1d7

WMDRMPD http://www.divshare.com/download/4003086-013

REFS--no files

and put them in into 1 folder named SYSTEM--make it hidden then put it on sansa

then create a music folder make it hidden

then create photo folder with thumbnail and my album folder make my album hidden

then create pictures folder make it hidden

then create playlists folder make it hidden put this file in it
http://www.divshare.com/download/4003139-94b

make a record folder with 2 folders named radio and voice

make a folder video

captilize all these except the one listed below

make a tmp folder

this should work :)