Whenever there is a "disk unknown not initialized” issue occurs, your hard drive may show unallocated space in Disk Management, and the data on which will be inaccessible or else there is another situation: there is no disk space shown in Disk Management.
Below are the 2 different methods to resolve the issue:
Method 1. Use Disk Management to fix not initialized error on an external hard drive
- Connect the uninitialized external hard drive to your PC.
- Press Win + R keys, type: diskmgmt.msc and hit Enter.
- Find the uninitialized, unknown external hard drive with I/O device error > Right-click on it and select Initialize Disk.
- Then set the disk to initialize and set the disk as MBR or GPT.
After this, you may reboot your PC and keep all changes. Now, your external hard drive will be recognized and read by Windows again.
Method 2. Run CMD to repair I/O device error on not initialized external hard drive
This CMD command would erase all data on the uninitialized hard drive, which you can later restore after repairing the external hard drive not initialized, with the help of any data recovery or partition recovery software:
To recover your data from the affected drive you need the help of reliable data recovery software. Here, I suggest you to check out Stellar Data Recovery Professional Software to recover your data from the affected drive.