> Serious error occurred - traceback follows
> ------------------------------------------
>>>> Error X'00280073' opening file C:\LISTSERV\MAIN\LISTADMIN.LIST <<<
> -> Severity: Error
> -> Facility: LFxxx routines
> -> Abstract: Internal file structure corrupted

It means somebody edited LISTADMIN.LIST with Notepad or the like. This is a binary file, it should never be edited manually. An alternative explanation of course is that the hard drive got corrupted, but in practice that only happens with FAT partitions. Nowadays even El Cheapo drives either deliver correct data or die, at least that has been my experience.

You should restore the file from your last backup.

  Eric