hii, I have a 500GB transcend external hard drive (Storejet 25M2) which I cannot access it.The problem is I cannot see it in My computer but is visible in Device manager
When I plugged in it asks me to format the drive.Disk management screenshot is on the link below
The Partition on that drive says it has a RAW File System. What this really means is that some of the data for that Partition is corrupted so Windows can't figure out how to use it. But VERY likely all your old data are still there.
anonymous1 asked the important first question. If you are SURE you do NOT want to recover anything from that HDD, you can wipe it clean and start over with an empty HDD. This can be done using Disk Management. You would RIGHT-click on that G: drive and Delete it. Then you would right-click again on the resulting Unallocated Space block and Initialize the drive, just as if it were brand new and empty.
HOWEVER, If you want your data back, you MUST NOT do that! You will need some data recovery software, and probably a spare HDD of at least 500 GB space. At least, you will need that spare temporarily. That is because most data recovery software will COPY everything it can recover to a different drive - it will NOT try to make any changes to the corrupted drive itself. AFTER the reliable copy is made, you can wipe clean the corrupted drive, re-Initialize it, and copy your data back to it. Then you can release the temporary drive to which all that data was originally copied.
There are several data recovery software packages available. Some are freeware, and some you must buy. Two I have heard of are Recuva and GetDataBack NTSF.
I also agree with what Paperdoc has written. But I think I need to add one more thing for your convenience.
As to the data recovery software, I think I can give you some suggestions. Actually, if you are luck enough, you can try free drive recovery software that have helped my brother retrieve all his inaccessible data back from a memory card. It works well on a drive and a memory card. Therefore, I recommend it to you and hope it will help you out, too.
After this trouble, you should learn to back up your important data all the time.