External hard drive can not be read by the computer

Hard drives won't safely eject if there's any program working with any files in that hard drive. For example, if you have a word document open from that hard drive, it won't eject.

Hi,
I've got bad news for you . Your hard drive is damaged for sure and you will need to replace it . It's totaly impossible to install a OS on a damaged drive and at least not recommended .
To retreive data , you will need to disconnect the drive and read it in a external box from a healthy computer .
The chance that the issue would be due to a defect SCSI connection is extremely small .
Regards .

i heard the external hard drives by seagate have issues

yah you must buy a Y-USB cable for your external hardisk. this is connection both ends are one is for hardisk and the other two cable is for USB slot of computer. why it two wires connection to usb because one wire is for Data and the other is for Power. If doesn't work..it might be a problem in your Operating system. i recommend to you to reinstall your Windows OS.. theres a 4 reasons why it happen appear the error... deffective USB cable..corrupted driver of USB device for seagate, virus infected of your systems..and maybe your hardive is deffective. Please rate if this is HELPFUL..thanks

The best way to recover your data if you cannot boot up your computer. Remove the hard disk and attach it to an USB hard drive adapter. Plug this adapter into a working computer's USB port and this computer should see this as an external storage device. You can then open the folders and files to backup/copy, provided the hard drive is not faulty.

Well depending on weather it is the EXTERNAL electronics, or the INTERNAL electronics, you can replace the circuit, board, with a new board from an exactly the same drive may work. But if the fault, is within the HDD's electronics, then the only way to fix that is to send it back to the maker and ask them to recover it, this can be very expensive though.

I called apple about this and they said there is no mac driver, that a mac should read a seagate external hard drive without any driver. My file system was ntfs.

This seems to happen when it's been connected to another computer. Are you running FreeAgent Sync? If so force a sync and the read only problem should go away.

Download Test Disk and try to recreate the boot sector

The problem is that u have done partitions for 160 GB harddisk, so do all the partitions of 40 GB or less than that.