This method, which you can follow to solve the “The disk is write-protected.” problem.
(If the above method does not work for you);
Follow the below steps:
1) Copy all the important data from this drive to your computer because this method will format the drive and erase all the data on the pen drive.
2) Now download the => Apacer Formatting Utility => unzip this utility to a folder on your hard disk, preferably on a folder on desktop screen for easy access (Do Not Try To Save it on pen drive), => Keep your pen drive plugged in, and double click on the Start. bat file in the folder where you unzipped the above utility => This will start formatting your pen drive, wait till the formatting completes and the LED on your USB stops blinking. Remove your pen drive after than and plug it in again.
=> The above two steps will solve the problem. If you still face the problem, follow the below steps:
1) Goto Start => run, type “cmd” and press enter, this will open command prompt.
2) Type the following command on the command prompt replacing X with the drive letter of your USB.