Hey there, @Sprouts2013!
I'd strongly recommend you test the HDD's health and SMART status by running
the brand-specific diagnostic tool or a third-party alternative before you do any data recovery attempts by yourself. It might also be a good idea to check how it will get recognized if you connect it to a different computer/USB port and using a different USB cable as well! If the HDD is dealing with any sort of physical (hardware-related) damage, you might actually do more harm than good to the data by trying to retrieve it using third-party data recovery tools.
If the files are really important to you, I'd advise you to consider contacting a professional data recovery company for assistance instead. They would be your best bet on getting any of those files back.
If the HDD is in RAW format, it indicates that the file system got corrupted. After testing the health and determining what is the SMART status of the external, you could try using a
Ubuntu Live CD as a last resort. I've seen it helped a lot of users dealing with the same issue, but you need to to know what is the physical/hardware condition of the drive first.
Keep us posted & good luck!
SuperSoph_WD