The normal file system is NTFS and unless the user did something like lock it down with EFS or shudder, some third party encryption the only limitation I've encountered is the drive may be READ ONLY. Hidden files may be inaccessible but back to some PC and remove that and back to the Mac.
http://www.lostpassword.com has a tool to deal with EFS key loss (which anyone that uses EFS knows to backup that key.)
http://www.drivesavers.com can deal with most other encryption so call them up if you don't know what you used.
Bob
Hi - I own a Toshiba X200 laptop that recently suffered a video card failure. As it seems to be near impossible to find a repair avenue I have pulled the harddrive out of the lap top and would like to access some files from it. I have purchased a USB drive case for it and have plugged it into my MAC laptop. I can now see the drive and many of the files on it but all of the "sensitive directories" cannot be read. I do believe it is a security issue .Anybody have any idea on how I can access them. I do still have the laptop password but have no idea how to connect to the drive using any credentials.

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