Mount "Item not found"

Q u o t e:
Last night I leveled to 60 and bought my journeyman training, then I obtained a black war tiger through PvP marks I had saved but when I tried to use my new mount it said "The Item was not found". I thought It might have just been the PvP mount so I went and bought a Swift Stormsaber but again- when I tried to Learn it, it also said "The item was not found". What should I do?

When you learn a mount - it should show up in your pet tab - and normally it disappears from your inventory (there are a couple exceptions for special ones on this, but these they should).

Is this when you are trying to learn them, or use them?

If it is when you are trying to use them - or you doing it directly from the mount tab? If you've hotbarred these, was it from the mount tab, or did you pull the item over before you learned them?

This is exactly the message you'd get if you hotbarred the item and it no longer exists because it was learned and is now in your mount inventory.

Q u o t e:
Its when I tried to learn them. They're both in my inventory at the moment.

I'd recommend first, trying a reset UI. There may be some conflict causing this.

To do a full reset UI, you will want to save your addons in another spot if you wish to preserve them.

Then rename/delete or move your WTF, Cache and Interface folders while WoW is shutdown. Reboot your system.

Note, if you are running Vista make sure your permissions are set so it does not undo your changes.

More detailed instructions for different operating systems, including Macs are here.

http://us.blizzard.com/support/article.xml?articleId=18761&searchQuery=reset%20UI&pageNumber=1

If that doesn't seem to correct things, I'd recommend submitting a petition on this next. Please do be specific in your petition as to exactly which mounts this seems to be happening on.