WS-110 will not turn on

Hello Press the FOLDER button to choose a folder
Press and hold ERASE button for 3 seconds or longer.
The ERASE indicator will flashes
Press the ERASE button again.
Done blinks for two seconds and the deletion will be complete
Note AN erased file cannot be restored.
During this process don’t remove batteries. Otherwise data may be damage.
The recorder should be formatted using only by using the internal FORMAT function found in the recorder's Menu. Formatting using the computer may corrupt system files needed to run the recorder, so computer formatting is not recommended

HI,

Please click on below link for user manual:

http://www.fixya.com/support/p144105-olympus_ws_100_handheld_digital_voice/manual-2304

Hello Press the FOLDER button to choose a folder
Press and hold ERASE button for 3 seconds or longer.
The ERASE indicator will flashes
Press the ERASE button again.
Done blinks for two seconds and the deletion will be complete
Note AN erased file cannot be restored.
During this process don’t remove batteries. Otherwise data may be damage

go here:
http://www.olympusamerica.com/files/oima_cckb/WS-110_WS-210S_Instructions_EN.pdf

You can download the user manual of OLYMPUS WS-110 HERE ( http://www.olympusamerica.com/cpg_section/cpg_support_manuals.asp?id=1321).

TO DOWNLOAD THE BROCHURE CLICK HERE

Audio files need the right codecs to play them. Windows media player generally needs these to be added. Download the K-Lyte CODEC pack from the Major Geeks website. Always use the advanced mode when installing them, as they do like to change your browser settings or change your browser completely if you do the normal way.

well, i resolved this myself by going to the sub-menu, and formatting the recorder to its original state. thankfully, i backed up the files on my computer first, so i didn't lose any data, although i did have to go in and re-set all my preferences on the recorder.
lesson: don't MOVE files from recorder to computer. copy them instead, and do the actual erasing from the physical recorder itself.
i don't know if this was the most elegant solution, but at least it did get my recorder up and running again. i'd love to hear if there is a better resolution out there.

The two parts are each shaped like L's. While holding the release button, pull the two parts away from each other.

WS-110 is not really MAC friendly.
Olympus says:

"The WS-110 can be used on a Macintosh computer that has Windows Media Player for Mac installed. Windows Media Player for Mac can be downloaded for free at Microsoft’s web site. The WS-110’s files are not compatible with iTunes. If the files are opened using iTunes, they will become corrupted and rendered unplayable."
From Support > WS-110

you can download Windows Media Player for Mac here: Windows Media Player 9 for Mac OS X

you can copy the file you want (not move) and then erase it using the buttons on the device itself.