This is probably because the file is a binary file that is intended to be placed on an HP NonStop Server. The number after the comma represents the NSK filecode for the file. Example filenames are:

    REL8INST,100
    ZINSTALL,100

If, after downloading the file to your PC, you FTP it to your NSK server, then the filecode of the file on the server will be set automatically. If you use another method to upload it to your NSK server then you must manually set the filecode using a FUP command, such as:

        FUP ALTER ZINSTALL, CODE 100