I know you have read through that document and carried out everything that it most likely has told you to do, however can we just briefly go through this following checklist?
The audio file is a .raw file that is at 8000 sample and 8bit
You have update the RingList.xml file?
You have updated the DistinctiveRingList.xml?
You have updated the tftp-server list on the configuration file that points to the files exact location?
You have run the debug tftp event command to see what happens when you try to choose that file?
A good thing to make sure is that the file extension is not .RAW and is a .raw, you would be amazed how many people fall into this trap.
The important thing is to see what happens in the debug when you try to choose the file, normally when it says that the file is unavailable, it is saying that because the XML lists it but the file can not be found, so this points to a break in the reference points (Symbolic Links).
using the latest updates package and a 7945 phone
This is the phone i use daily and do all my testing on, for some reason it would not pick up the CTU24.raw file that i put in until i reset the phone, it just kept on saying unavailable when i chose it in the list, so maybe even try that.
**When you rate a persons post, you are indicating a thank you or that it helped, but at the same time you are also helping to maintain the community spirit - You don't have to rate posts and you wont be looked down upon :) *
Configure Multicast Paging on the Cisco IP Phone 7800 Series or 8800 Series Multiplatform Phone
The Cisco IP Phone 7800 and 8800 Series Multiplatform Phones provide voice communication over an Internet Protocol (IP) network...
Add Call Park on a Cisco 7800 or 8800 Series Multiplatform Phone Key Expansion Module
Call park allows the user of the phone to put an incoming call on hold so that the call can be retrieved on another phone. A call is park...