Hi,
From this link
http://uc500.com/where-are-voicemail-wav-files-stored
These files are indeed on the Unity Express ISM, but are unfortunately well protected from any kind of user interference. You can't reach them, alter them, delete them, anything. The entire voicemail application and its datafiles (including voice prompts and the messages themselves) are very protected by Cisco.
The only thing you can do, is upload new language packs from Cisco.
HTH
Alex
Regards,
Alex.
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