OS X 10.8.2, early 2009 Intel Mac Pro. Build 4762 will not load fonts dragged from an external hard drive to the open window no matter what format they are in.

If I copy them to the Desktop, then they will load.

More info about that:

If they are in a top level folder of the external, they will load. Anything deeper, no.

That's very interesting. Will check this.

Let me clarify something here about my use of the word "external".

To my way of thinking, it is an external because it is not on the System drive, rather it is one of eight partitions on one of four hard drives within the machine. It is not physically outside, attached via cable.

There may be some file access permission issues. I myself have my user folder on a 2nd partition and it works fine. I'll check what's happening if TrT is attempting to read from read-only files or folders.

Also, what filesystem is your partition formatted with? (Disk Utility should be able to tell you that)

I do keep all folders on my externals Read/Write; that's the first thing I looked at. All drives are partitioned as Mac OS Extended Journaled.

I'll do some more tests on this problem later today, and test also using my System partition though I don't normally use it for live work. I will also go through all the folders and check Permissions again.

I have an answer to the problem. It has to do folder naming.

I had a folder with a name that included a TM symbol; that's what was breaking the process although it shouldn't be.