Preferences does not scan for media, it only changes the storage location for new additions. The files have to be added to the library. Pgm file. It sounds like you tried this in one of your attempts but it did not work (I don't know why it didn't unless there is some detail I missed).
- Mac Computer Not Recognizing External Hard Drive Xbox One
- Windows Not Recognizing External Hard Drive
- This video shows how to fix external hard drive not detected in Windows 10 due to no drive letter. Windows 10 Pro License: (20% Coup.
- When USB ports are not recognizing devices it can be an indication that you need to reset the System Management Controller (SMC) on your MacBook Pro. The SMC is responsible for low-level functions like the USB power. Try the steps in the article below, and let me know the results. How to reset the System Management Controller (SMC) on your Mac.
The most direct reason why an external hard drive is not detected by computer is a broken USB port. You should try to connect the hard drive via another USB port or on another computer. If the USB device not recognized problem is solved, it is the USB port that should be blamed.
Where do you want your library? On the external or internal?
H40 parts manual.
![Mac Mac](https://i.ytimg.com/vi/d7BPELPk9Z8/hqdefault.jpg)
If the internal, start iTunes. Drag your media files to the 'Automatically Add To iTunes folder. iTunes 9: Understanding the 'Automatically Add to iTunes' folder. - http://support.apple.com/kb/HT3832 Or use the 'Add' menu item to add files to iTunes, or drag them to the iTuens library in the sidepanel.
If somewhere else, start iTunes while holding down the option/alt key, select a library location. Add as above.
What are the iTunes library files? - http://support.apple.com/kb/HT1660
More on iTunes library files and what they do - http://en.wikipedia.org/wiki/ITunes#Media_management
Mac Computer Not Recognizing External Hard Drive Xbox One
What are all those iTunes files? - http://www.macworld.com/article/139974/2009/04/itunes_files.html
Where are my iTunes files located? - http://support.apple.com/kb/ht1391
Windows Not Recognizing External Hard Drive
Oct 1, 2014 6:37 AM