I copied the files direct into Notifications and they worked fine. App Gmail and Voice Mail use .wma format. Custom phone ringtones use .mp3. These are stored in the Ringtones folder. These can be copied direct to the folder also.
try a different file browser. i was having the same problem, i tried transferring the files again using the built-in file browser. worked like a charm. good luck!
This is a pretty long way to do it. Maybe things have change since then, when this was posted. The process can be a little les complicated. There's another way. First I use Zedge app to download ringtones or notifications sounds, very easy app. Once you download the sound you want, go to settings click on apps find messages. On the right side of message it will have the icon settings (If you don't see the icon on the side of messages, just click on messages, you should be able to see icon on top right) , click on it, you will find new messages, click it. You will find sounds, click it. Now you can select your sound or click on default notification sound. That's it.
Excellent! Had been trying to overcome the challenges of adding notification sounds and had to take a moment to share some appreciation for posting this. Man, they couldn't have made that more convoluted! Well, may they could... - Thanks again!
To recipricate, I found these notification sounds which are a bit more professional, rather than crazy. Also thought the story behind why these are now free was a respectful gesture: https://theinteractivist.com/free-ringtones-iringpro/
