I have a 2013 Macbook Pro, 2.6 GHz Intel Core i5, 8 GB 1600 MHz DDR3, 250GB storage, OSX El Capitan v10.11 Using a Seagate 4TB external HDD, and plugged it in today to find in my media folder files only going up to the letter 'G'. - Tried searching for the other files but couldn't find them. - Tried copying a file in with the same name as one of the unseen ones, get the message 'A newer folder named “Folder Name” already exists in this location. Do you want to replace it with the older one you’re copying?' - When dragging a new file or folder in the media folder, it disappears, no matter what letter it begins with. - When moving files from that folder into another one, some files started to appear past the letter 'G', and got up to 'J' but then files were disappearing from the media files that were already in the folder (files with names beginning before 'G') - HDD recently had another problem. Was working 100% fine from the day I bought it, but then suddenly could only read and couldn't write. Apparently it's NTFS. I couldn't format it to FAT32 because there's so much data on there that I couldn't back up. Found a solution on the internet to change permissions so now the HDD can write as well even though it's NTFS. Worked fine after that until now with this one media folder. - One of the files briefly had the error message 'The Finder can’t complete the operation because some data in "Folder Name" can’t be read or written. (Error code -36)' when trying to drag to a new location. Not sure what happened, but that folder can be moved now. Had a feeling that might have been the folder that was causing the other problem? Not sure, but it's all been very strange. - Tried using Revealer and terminal commands to show hidden folders. - Get Info on the media folder shows 'Zero KB' of data Please help!!!