If there is some kind of corrupted file on your Chromebook that cannot be opened or deleted, it would be a good idea to find out which device contains the file. You need to open the Files application, find the particular file, and try to move it to the Trash by deleting it using the usual procedure. In case the file is located within the Google Drive account, you need to check your Internet connection and manage the problem using the Google Drive website. In case the file is stored on an external drive, such as a USB or SD card, it is necessary to safely unplug and plug in the device to see whether it is accessible from another computer. Formatting should not be done as the first step since it will erase other information as well. Notchox, a data recovery software is able to scan supported external drives on compatible computers.