How to restore portale external drive back to normal when it reads corrupt

Hello,
I have a seagate portable external hard drive and when i hook it up to my laptop it readsy corrupted and unreadable...then it asks do you want to format...but i know format would change it back to factory setting right???
Help

Format would eliminate all your files. Does it show up in windows disk management? If so, does it have a drive letter? If not, right click on the drive in disk management on the right side of the page and give it a drive letter.

If it actually is corrupted, like from disconnection during a write, you still may be able to salvage some files with a disk recovery tool -- there are a number on HIREN's BOOT DISK, which you can download HERE.