Recovering 4mm tar tapes

[Douglas Taylor]

I have a pair of 4mm DDS tapes from 1999 that I would like to recover.  
I was able to read one with tar on a Debian (jessie) Linux system, but 
the second gives an error.

The tape that I could read is a Sony with DDS markings and 4 bars next 
to the DDS logo.  It was written on an SGI computer. I was able to read 
this with a simple tar -xvf /dev/st0 command.

The second tape is a 3M brand with DDS markings and 4 bars next to the 
DDS logo.  It also has 'Media Recognition System' and DD-90 written on 
it.  Here is the dialog and error:

root at T5400deb:/home/taylor/4mm_tar_1998# lsscsi
[0:0:4:0]    disk     codesrc          SCSI2SD  4.2  /dev/sdc
[0:0:5:0]    disk     codesrc          SCSI2SD  4.2  /dev/sdd
[0:0:6:0]    tape    ARCHIVE  4326XX 27871-XXX 0324  /dev/st0
[3:0:0:0]    disk    ATA      WDC WD800JD-75MS 1E04  /dev/sda
[3:0:1:0]    cd/dvd  PLDS     DVD+-RW DH-16A6S YD11  /dev/sr0
[4:0:0:0]    disk    ATA      ST500DM002-1BD14 KC45  /dev/sdb

root at T5400deb:/home/taylor/4mm_tar_1998# mt -f /dev/st0 status
drive type = 114
drive status = 318767616
sense key error = 0
residue count = 0
file number = 0
block number = 0

root at T5400deb:/home/taylor/4mm_tar_1998# tar -xvf /dev/st0
tar: /dev/st0: Cannot read: Input/output error
tar: At beginning of tape, quitting now
tar: Error is not recoverable: exiting now

The tape drive is a Seagate CTD8000R-S with COMPAQ markings. There are 5 
jumpers to configure the drive and one is for MRS which the jumper 
config page I have says it is enabled (Default), however the pins are 
missing for that option.  What does that mean?

(None of the config jumpers were installed for the tape that I could 
read)  Is the 2nd tape just bad and can't be read?  Or do I need a 
slightly different tape drive?

Doug