We're running Photoshop CS4 on a Mac running Snow Leopard 10.6.4. Whenever this user tries to save a .JPG (any JPEG) as a .TIFF, she gets this message. I've tried all the standard stuff. Getting rid of preference files, reinstalling CS4, patching it up to the latest revision. This is a brand new computer -- plenty of RAM, hard drive space, and nothing else is running while we're trying this.
I searched all over, but most of the docs I found were related to CS2. I tried the troubleshooting steps in them anyway, but they didn't help. I was looking for maybe a Photoshop log of some sort, that might have more detail in it, but I have no idea where to find it.