Hi Terry, I suspect the portable drive is FAT32 at point of sale and you didn’t format it to NTFS, and this is causing file corruption because the computer you connect it to is NTFS. Connecting a Maxster FAT32 portable hard drive to an NTFS system will corrupt files on the portable drive. Those files and folders you can’t get into are pretty much lost, but the folders that you can gain access to can be backed up onto your main computer before doing the format. Peter -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.308 / Virus Database: 266.8.1 - Release Date: 23/03/2005