Erased the data on this drive... now it will not mount on my computer?????

You could try data rewriting software to erase your data, like AOMEI Partition Assistant Erase hard drive feature: http://www.extend-partition.com/help/wipe-data.html first you need to connect this disk on your computer and then download the free version of Partition Assistant to use.

Instructions

1. • 1

     Open the system drive, usually titled "Macintosh HD." Open Applications, then Utilities and double click the "Disk Utility" program to open it. A window will open giving a list of all the drives currently mounted on the computer.
     

   • 2

     Select the disk that needs to be formatted on the left. It is not possible to format the startup disk unless the system has booted from the Install Disk. It is important to note that formatting the startup disk will permanently erase the data stored on the disk. If you are planning on erasing the startup disk, back up all important files and applications.
     

   • 3

     Click on the "Erase" tab to the right of the list of drives. The window will now display the options for erasing the hard drive and formatting it to work on the Macintosh computer.
     

   • 4

     Select the Volume Format from the pop-up list. In most cases it's best to leave it at "Mac OS Extended (Journaled)" as this is the default. This setting is the best option for running Mac OS X. If there are other requirements for the disk, then select the format that best suits your needs. If you have questions about the formats, refer to the Apple user's manual.
     

   • 5

     Name the hard drive. Type a name for the disk in the field where it asks for the name. This name will always appear when the disk is mounted on a Macintosh computer.
     

   • 6

     Click the erase button. A window will open asking to verify the erase procedure. Click the erase button in this window to start the process of erasing the disk. Once the process is complete, the drive will appear with the name it was given on the left side of the window with the list of drives and on the desktop of the Macintosh computer.
     

1 . Open the system drive, usually titled "Macintosh HD." Open Applications, then Utilities and double click the "Disk Utility" program to open it. A window will open giving a list of all the drives currently mounted on the computer.

2. Select the disk that needs to be formatted on the left. It is not possible to format the startup disk unless the system has booted from the Install Disk. It is important to note that formatting the startup disk will permanently erase the data stored on the disk. If you are planning on erasing the startup disk, back up all important files and applications.

3. Click on the "Erase" tab to the right of the list of drives. The window will now display the options for erasing the hard drive and formatting it to work on the Macintosh computer.

4. Select the Volume Format from the pop-up list. In most cases it's best to leave it at "Mac OS Extended (Journaled)" as this is the default. This setting is the best option for running Mac OS X. If there are other requirements for the disk, then select the format that best suits your needs.

5. Name the hard drive. Type a name for the disk in the field where it asks for the name. This name will always appear when the disk is mounted on a Macintosh computer.

6. Click the erase button. A window will open asking to verify the erase procedure. Click the erase button in this window to start the process of erasing the disk. Once the process is complete, the drive will appear with the name it was given on the left side of the window with the list of drives and on the desktop of the Macintosh computer.

If it is not seeing it then you will need to format it properly for Mac's most hard Drives are pre-formatted for PC's.
You also need to make sure the SATA cable is plugged into the right place on the board.
SATA Hard Drives do not need a pin out. Only IDE drive's have that function.

If this is an addon drive then


Open the system drive, usually titled "Macintosh HD." Open Applications, then Utilities and double click the "Disk Utility" program to open it. A window will open giving a list of all the drives currently mounted on the computer.

Select the disk that needs to be formatted on the left. It is not possible to format the startup disk unless the system has booted from the Install Disk. It is important to note that formatting the startup disk will permanently erase the data stored on the disk. If you are planning on erasing the startup disk, back up all important files and applications.

Click on the "Erase" tab to the right of the list of drives. The window will now display the options for erasing the hard drive and formatting it to work on the Macintosh computer.

Select the Volume Format from the pop-up list. In most cases it's best to leave it at "Mac OS Extended (Journaled)" as this is the default. This setting is the best option for running Mac OS X. If there are other requirements for the disk, then select the format that best suits your needs. If you have questions about the formats, refer to the Apple user's manual.

Name the hard drive. Type a name for the disk in the field where it asks for the name. This name will always appear when the disk is mounted on a Macintosh computer.

Click the erase button. A window will open asking to verify the erase procedure. Click the erase button in this window to start the process of erasing the disk. Once the process is complete, the drive will appear with the name it was given on the left side of the window with the list of drives and on the desktop of the Macintosh computer.

I got these instructions off ehow.com

hi.

follow instructions below
1> Open the system drive, usually titled "Macintosh HD." Open Applications, then Utilities and double click the "Disk Utility" program to open it. A window will open giving a list of all the drives currently mounted on the computer.
2> Select the disk that needs to be formatted on the left. It is not possible to format the startup disk unless the system has booted from the Install Disk. It is important to note that formatting the startup disk will permanently erase the data stored on the disk. If you are planning on erasing the startup disk, back up all important files and applications.
3> Click on the "Erase" tab to the right of the list of drives. The window will now display the options for erasing the hard drive and formatting it to work on the Macintosh computer.
4> Select the Volume Format from the pop-up list. In most cases it's best to leave it at "Mac OS Extended (Journaled)" as this is the default. This setting is the best option for running Mac OS X. If there are other requirements for the disk, then select the format that best suits your needs. If you have questions about the formats, refer to the Apple user's manual.
5> Name the hard drive. Type a name for the disk in the field where it asks for the name. This name will always appear when the disk is mounted on a Macintosh computer.
6> Click the erase button. A window will open asking to verify the erase procedure. Click the erase button in this window to start the process of erasing the disk. Once the process is complete, the drive will appear with the name it was given on the left side of the window with the list of drives and on the desktop of the Macintosh computer.

regards

If problem is with drive, this may not work. If problem is with enclosure, you have to open the enclosure, extract the drive and get a HDD dock (usually around $15-$30) and access the drive that way.

Disk UtilityTo completely erase a Macintosh hard drive that runs OS X 10.3.x or above—not just individual files on the drive—you can use the Disk Utility that is built into the Macintosh operating system.

How to Use Disk Utility to Erase a Macintosh Hard Drive (OS X 10.3.x or 10.4.x)

1. You must reboot your computer using the OS X system CD that came with your Macintosh. To do so, follow these steps:

• Insert the CD into the CD drive.
• Hold down the C key during the startup process.

1. Select your preferred language. You will then see the Welcome to the Mac OS X Installer window.
2. From the Installer Menu Bar, click Open Disk Utility. You will then see the Disk Utility window.
3. In the left pane of the Disk Utility window, click the drive you want to erase.
4. In the right pane of the Disk Utility window, click the Erase tab.
5. From the Volume Format drop-down menu, select Mac OS Extended (Journaled).
6. In the Name field, highlight the existing text and type the name the hard drive is to be called after it's formatted.
7. NOTE: If you ever plan to connect another computer running OS 9 to this hard drive, you'll want to install the Mac OS 9 disk driver, so that this disk will be visible from an OS 9-booted computer. If you don't know if you will do this in the future, it's best to install these drivers.
   
8. The following are the available security options:

• Don't Erase Data—This option only rewrites the headers on the disk. Files can be recovered by forensics, disk utilities, and other advanced recovery software.
• Zero Out Data—There are forensics utilities that, albeit expensive and time consuming, can retrieve zeroed-out data.
• 7-Pass Erase—This is considered sufficient by government standards to erase data from a disk. It writes random data over the disk seven times. It may take several hours or more to complete this process.
• 35-Pass Erase—This makes it absolutely impossible to regain any data off the drive. This option takes an extremely long time, possibly more than one day.

1. Click the radio button in front of 7-Pass Erase (recommended by UD).
2. Click OK.
3. Click Erase.
4. Confirm you want to erase. The program will unmount the volume, partition the drive, and rename the volume to the name you typed in step #7 above.

hi,if you want to erase all the data can your format it?
or try to erase data on another computer
hope this helps :-)

If you goto My computer and click on the Appropriate Letter for your flash Drive you can then Right click on it and go to "FORMAT" and then from there click Ok or Next. This will erase all data on the flash drive. You can also physically open the drive in my computer and select everything by pressing CTRL and A at the same time and then pressing the DELETE key on your keyboard, either one works fine and will delete the data off of a flash drive. Hope my answer gets you closer to a solution. Please Help rate me if I helped you out or not I am new but a very good tech.