20 Most Recent Western Digital 250GB My Book Pro-External 250 GB Hard Drive Questions & Answers

Try the drive on a windows machine and a Linux machine. It depends on the drive has been formatted. If ex fat or fat then it should be read on a mac ok. If NTFS or Fat 32 then a windows machine should see it.

narnia1963

Most like the issue is that the drive letter that your external drive wants is already assigned to another device. The link below will help you change the drive letter.

Let me know if you have any more problems or questions

Issken
http://www.fixya.com/users/issken

How to change your drive letter in Windows XP
http://www.fixya.com/support/r4183994-change_drive_letter_in_windows_xp

How to change your drive letter in Windows Vista and Windows 7
http://www.fixya.com/support/r4176803-change_drive_letter_in_windows_vista

If it still is under warranty, exercise the warranty, and get a replacement.
If the warranty has expired, disassemble the case, and extract the disk-drive. Connect that disk-drive as a "slave" disk-drive in some desktop computer, and see if the disk-drive is still functioning, and if the files on the disk-drive are still readable.

You should not even try to install an operating system on an external drive. Windows looks at the "C" drive and installs programs to "C" drive. You are trying to put it on the "G" drive. You will have too many problems and wish you never had tried. Buy a larger main drive and partition it with two equal partitions. Then "Dual Boot". You will find how to do this on the internet. Just Google "Dual Booting".

Get TESTDISK and see if it is recognised, if so TestDisk has some tools that may help

If your HARD DRIVE was exposed to a magnetic field, this can happen.
Try a scandisck run.
Boot up in safe mode and run fix disk.

The hard disk is having bad sectors on its first 3000 sectors.the bad sectors are caused by degradation of the platter of the hard disk.OR the factory area of the hard disk has certain files called SMART, G -LIST and other log files.Unless one empties those log files with a good tool , one cant format ones hard disk.

This is likely a couple problems; 1. The hard drive is dying or is dead. You're looking at hardware recovery if this is the case. There are some tools such as Spinrite that might be able to recover the disk. (GRCHard drive data recovery software) 2. The power supply on the computer/laptop is not functioning as well as it used to. Try using another PC to see if there's any difference in results.

Download testdisk and run it to see if it recognised in the list. If so use the intel option to find a boot sector

Remove the drive from the external case it is in and connect directly to your computer - see if the bios recognizes it. If so, the OS will do so also and you can access it. Also means the electronics of the external case are no good. If not recognized in other machine, the hard drive has gone to hard drive heaven and needs to be replaced.