ubuntu 16 load, 18 does not from harddisk nor usbstick nor live cd

[polbruw]

last year i did receive an update (for ubuntu 18),from then no load possible from harddisk nor live cd. only live cd and usb stick ubuntu 16 did load wthout any problem. i did a lot af tests all good but..... if i try to install a do receive "still uncorrected error.... aborted. today i see that i can sent a report (is sent some minutes ago) for help. hope you can help me out of this problem.
pc is dell optiplex gx280 ( ubdates are stopped for this machine as it uses i383 (?i think)
thanks for your time best regards
pol.
bug report is already sent some minutes ago from the pc

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: ubiquity 2.21.63.10
ProcVersionSignature: Ubuntu 4.15.0-45.48~16.04.1-generic 4.15.18
Uname: Linux 4.15.0-45-generic i686
ApportVersion: 2.20.1-0ubuntu2.18
Architecture: i386
CasperVersion: 1.376.2
Date: Fri Jan 1 09:28:09 2021
InstallCmdLine: file=/cdrom/preseed/ubuntu.seed boot=casper only-ubiquity initrd=/casper/initrd quiet splash --- nomodeset keyboard-configuration/layoutcode=be
LiveMediaBuild: Ubuntu 16.04.6 LTS "Xenial Xerus" - Release i386 (20190227.1)
ProcEnviron:
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)