Indeed, let’s see if we can clear your player up.
First, do you have a v1 or v2 player? They behave a bit differently. Corrupted files (especially ones that hang up the player) can be corrected if you connect in MSC mode , then use the chkdsk utility or the check volume for errors function under manage from the PC.
Here’s some information for you regardingfile corruption.
The most common source of duplicated tracks when using Windows Media Player is when you have different versions of the same track, encoded in different formats. The player will list both versions in sequence. If you mount a microSD card with some tracks that are also stored in the player’s internal memory, you’ll also have duplicates displayed on the Sansa.
If there are files that are not erasable from the player, let me know which version device you have. The v2 e200 has a different splash screen, a SanDisk logo with refleation below, plus a blue sansa logo that appears below that, when the device is turned on.
If you manually erase your music from the PC, the e200 will allow access in only one USB mode at a time. If you transfer some files in MTP, then in MSC, erasure of files from the PC is only possible for the files transferred in the same mode. It’s possible that there are files that were transferred in the other mode.
The music database of the player is another point of contention. This index file is normally appended with successive transfers, to save time. You can delete this file, forcing the Sansa to build a new one from scratch the next time it’s powered up or is disconnected from the USB bus. On the v1, this is the DATA folder, and on the v2, it’s a file named MTABLE.SYS.