Cannot access files

[faizsaiyad]

Hi guys,
I need some help. I have aseagate 1TB ext. hard drive. I cansee it as G drive bit cannot access the files. Strangely I did get the same issue some time back and I ran th seagate tools and the bad sector was resolved. This time I was trasfereing the video files and after completing the task the drive is visible in my computer but I cannot access the files. Whole lot of data is stuck and pretty important too. Kindly suggest a solution.
Windows 8 in use

Thanks in advance