A virus-proof diskless computer with data interface for filtering data is provided as a robust virus-proof user computer system. The computer system is provided without a hard drive such that the computer must boot from a disk every time the computer starts. In this way, the operating system and computer files will not be corrupted by the user's use of the machine. A data filtering interface is also provided that allows only certain data file types to be transferred through the data interface port. This will help prevent unwanted file types and viruses from being transferred to or from the computer system.