I seem to come across this 4 or 5 times each year during my Exchange UM deployments and I find that I always forget the answer having to look into my old notes so I figure I should take the time to write a post so I can just refer to it in the future for a quick answer.
So what file format and attributes does Exchange UM expect when you supply a wav file for an Auto Attendant prompt?
Attributes: 8.000 kHz, 16 Bit, Mono @ 15 kb/sec
More precisely, the settings should look something like this:
Bit Rate: 128kbps
Audio sample size: 16 bit
Channels: 1 (mono)
Audio sample rate: 8 kHz
Audio format: PCM
So what if you have a file that doesn’t conform to these settings? See this post: http://terenceluk.blogspot.com/2010/11/exchange-um-error-when-configuring-auto.html