Steps to format your new drive are as follows:
1. Right-click My Computer and select "Manage"
2. On the left pane, click on "Disk Management"
3. On the right pane, right-click your new disk and select "Format"
4. Dialogue box appears, choose your settings (Partition size, file system, drive letter, etc...)
Once that is done it should be in Explorer. Hopefully that helped. If not just post again with more details.
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