This message occurring during boot up of KNOPPIX-Live has no deleterious consequences but it is an annoyance.
It is probably an unintended hangover from the HD-installed version which allocates several partitions.
Either ignore it or include a (2nd and) 3rd (and 4th) partition in your boot device, even if it is a USB stick.
Use fdisk* to set /dev/{sda}1 as the KNOPPIX partition type c (being FAT32; or NTFS if you prefer - I've never tried this).
Set /dev/{sda}3 as type 83 (Linux) (at least 400M). Then format it as Reiserfs with mkreiserfs .
It's not obvious to me how (or even whether) the partition is used; but it is made available; and you will boot
without the annoying error message!
(*) Yes: you need to format your intended USB device - from a temporary KNOPPIX USB device is probably your most
convenient method ;o)
1984 APPLE MACINTOSH Model M0001 1st MAC 128K 40th Anniversary PICASSO KIT NICE
$4999.99
Apple Macintosh 128K M0001 Computer with Mouse, no keyboard. Case included. 1984
$510.86
Macintosh Platinum Mouse - Apple 128K 512K 512Ke Mac Plus Lisa IIe M0100 - NEW
$44.99
Apple Macintosh 128k 512k Plus Analog Board Capacitor Re-Cap Kit - US Shipping
$23.95
Vintage Apple Macintosh Classic 128K Application On New 400K Double Density Disk
$26.99
Apple IIe 128K Computer Only A2S2064 SOLD AS IS
$108.88
Apple Macintosh 128K M0001 Computer (1984) upgraded to 512, Power Mac G3 plus
$1000.00
Apple Keyboard and Cable for Macintosh 128k 512k Mac Plus RARE Vintage M0110
$169.99
RARE 1984 Macintosh 128K M0001 MacWrite MacPaint BOX Set 1st Mac Software WORKS
$399.99
Apple Macintosh Compact Mac Computer Carry Bag Case Tote - 128k, SE, Plus
$55.00