If the SD Card or hard drive is working slowly or even not working, cleaning drive and delete partitions is one possible solution either. It also could solve the problem that the drive can not be in the format or showing the wrong capacity.
This trick will also remove a partition that can not be removed by normal means such as Disk Management, a built-in disk partition in Windows. This process will completely erase the partition table of the disk to allow you to rearrange.
Warning: This process will completely erase the entire disk, so make sure you have a backup of the files in the disk or make sure no important files. For internal hard drive, make sure you select the correct partition, do not delete the wrong disk or partition.
1. Open Command Prompt (as Administrator)
Open Command Prompt as administrator. In Windows 10 or 8.1 simply right-click the Start button or press the Windows key + X and select Command Prompt (Admin).
In Windows 7 you need to find Commnd PROMT in the Start Menu. Type Command in Start Menu search bar Command Promt then right click and select Run as Administrator.
2. Use diskpart to clean the disk
We will use the diskpart command to do this. Before continuing make sure you connect the USB flash drive, SD Card or whatever drive you want to clean.
To run the diskpart type the following command to the Command Promt window and press ENTER:
Diskpart list displays connected to the computer by typing the following command and press ENTER:
Look carefully output of the command to identify the number of disks to be cleaned. Be careful here! If you choose the wrong disk, you will clean the wrong disk and you will lose important data.
In the image below we can see Disk 0 Disk 1 238GB and 14GB. We certainly know how much capacity of flash that is plugged into the computer. Here Disk 0 is the system drive (hard drive) and Disk 1 is the flash.
Once you know which disk to be cleaned when the following command, replace # with the number of disks that you specify.
select disk #
Now select the disk that you have defined. Any command that you give now applied on the disk that already. To completely remove a disk partition table that has been type the following command and press ENTER.
Caution: This will erase all data on the selected disk! Make sure you’ve backed up important data before proceeding!
You will see diskpart managed to clean the disc if everything is working properly. Now you’re done. Close the window Command Promt to proceed to the next step.
3. Partition and Formatting Disks
Now you should be able to access, partition and format the disk as usual using the supplied Windows Disk Management. You can also use the diskpart command to do this, but as it will be easier to use a tool that uses the interface.
To start the Disk Management in Windows 10 or 8.1 right-click the Start button and select Disk Management. In Windows 7 press the Windows key + R type diskmgmt.msc in the Run column, and press ENTER.
You will see a disk that has no partitions. Right-click that does not contain a space and select New Simple Volume to create a partition on the disk and format the file system you want. By default Windows will create a single partition spanning the entire drive.
If this does not work, for example, you managed to clean the drive but it does not function normally when creating partitions or if you can not read the disk diskpart possibility that the disk is physically damaged and do not work well. However, cleaning the drive with diskpart is a solution that can make a drive that seemed broken for most people to return to function properly.