Use a memory card reader to connect the microSD card to a computer for formatting. In case you're using an SD card adapter, ensure that the write protection key is in the unlock position.
Right-click My Computer, and click Manage. Go to the Disk Management tab on the left pane, and locate your microSD card from the list of available disks.
Right-click on the microSD card's drive, and click Format. This eliminates all data, including corrupted files that cause write protection in storage devices.