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If your USB flash drive, pen drive, or external mass storage device is enabled, then you won’t be able to copy any data from your computer to USB drives. To revert back or disable Write protection on USB flash drives, then follow the instruction:
1> Click on “Start –> Run –> type regedit and hit Enter”
2> Navigate to “HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control”
3> Create a new key and name it as StorageDevicePolicies
4> Select StorageDevicePolicies and create a new DWORD (32-bit) Value and name it as WriteProtect.
5> Set the value of WriteProtect to 0, this can be done by double clicking on WriteProtect.
Close registry editor and you are done. Sometimes you may have to boot the machine before the changes takes place. After WriteProtect is de-activated, users will able to write data from computer to any external storage device.