What Happens When I Initialize a Disk? I Need Help

I have a Toshiba 1TB external USB hard drive. Suddenly, it is now showing as Unknown, Not Initialized, and Unallocated. Then, I received the message which says 'You must initialize a disk before Logical Disk Manager can access it'. This notice sounds urgent, but I don't know whether it's safe to initialize a disk. What happens when I initialize a disk? Will I lose everything?

Hello, receiving such a message must be frustrating for you. Let me help you solve this problem. You need to initialize it before using a new disk. It is the process by which your disk is recognized by your PC. It usually involves:

• Assigning a drive letter for your new disk.
• Applying a partition style, whether MBR or GPT. Click to read on MBR vs GPT.
• Creating partitions.
• Formatting partitions.

According to your description, your Toshiba USB drive is not brand new. So, there might be some errors, such as MBR corruption and file system corruption on your USB. When you initialize it, your data will be erased while rebuilding the master boot record (MBR) and formatting the drive. You can turn to some data recovery software for help. 

To help you make your USB work again, I recommend EaseUS Partition Master Professional, a third-party disk management tool for you. You can have an easier initialization process as this tool is very simple to use. A few clicks is required to initialize it. Here is a step for you:

Step 1. Connect your USB to your computer.

Step 2. Run EaseUS Partition Master. Go to the "Partition Manager" section.

Step 3. Right-click your USB drive and select "Initialize to MBR" or "Initialize to GPT". 

Step 4. Click "Execute the task" and "Apply" to save the changes.

Simple and quick, your USB will be initialized with EaseUS Partition Master. I hope that you can fix the problem soon.