Depending on which pen you have, you may not have the reset option, however, if your computer recognizes the device and you are trying to format it is very simple. On a windows computer go to My Computer, disk management, or file explorer depending on your version of Windows and right click on the root folder (the device you are trying to reformat) click the word "format" and Select "FAT 32" under the File System and make sure Quick Format is not selected. (If you are not sure, just leave all the selections as default.) From there just follow the prompts until it is complete. If you are on a Mac system just go to disk utility and normal click on the device, from there on the right hand side you will see options to erase, format, partition, etc. Click on the one you want then follow the prompts