External HDD not recognised by comouter

Right click on computer and select manage, in the left column select disk management, look in the lower portion of the window. Do you see a drive with no drive letter assigned? If so, right click the drive, select change drive letter or path, next window select add, and add a drive letter. If it is a new drive, there should be nothing on it. it may want to 'initialize' it and format it. If it does and there is no data on it, do so, select new simple volume, and when finished it will be usable.

When you first get to Disk Management, you may very well be met with a pop up window that says a drive needs to be initialized, if that happens, click OK and follow the steps of creating a New Simple Volume.

Would you please Disk Management - Post a Screen Capture Image

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Let us take a look at it and see if we can't get you up and running.

Sanda, don't worry about the time differences, we are used to it. In the bottom left of your post, please click 'My System Specs' the system specs shown there do not match what you are showing, there will be a link there to update your system specs. Please fill that out to your current system and be sure to click save at the bottom of the page.

I assume you are having problems with drive 3. Right click it and if the option is there select new simple volume. Follow the prompts. If that option is not available, please tell us what options you do have. Assuming the disk is empty, if you have the option select format, you will want NTFS as a file system.

Also, unless it holds another operating system, Disk 1 should not be marked Active.

Have you tried mounting the drive inside the computer? What type of dock is it? USB esata?

I hope it works out well for you. If it's the docking station, take it back to where you bought it and tell them it doesn't work and you want a refund or a replacement that does work.