The files are stored in a Linux operating system and so are protected against data damage using the protection processes of the operating system.
Before upload, the file is encrypted using AES 256. It can only be decrypted if it is undamaged. The encryption process includes a checksum. This restricts even a part file from being decrypted correctly. Any damage of even 1 byte would result in a complete scramming of the output. This ensures transfer integrity to the very highest level.