New Acer Aspire 515-58PT grub2 ISO not booting

Ed_P

Acer Aspire 515-58PT, Windows 11 24H2 for x64

I boot ISOs. Have been doing it for yrs, no CDs, no DVDs, no USBs, no hdd partitions. I use Grub2Win for grub2 menus which I expand on my own. On my Windows 11 notebook these ISOs boot:

 set iso="/ISOs/PorteuX/porteux-v1.8-current-cinnamon-6.4.2-x86_64.iso"
 set iso="/ISOs/PorteuX/porteux-v1.9-current-cinnamon-6.4.6-x86_64.iso"
 set iso="/ISOs/PorteuX/porteux-v2.0-current-cinnamon-6.4.9-x86_64.iso"

with:

 search -f $iso --set=root
 loopback loop $iso
 linux (loop)/boot/syslinux/vmlinuz      from=$iso   # $bootparms
 initrd (loop)/boot/syslinux/initrd.zst

boot fine. On my Acer they do not. Porteux complains not able to find porteux.cfg file. Other ISOs boot fine, on both notebooks.

Any idea why these ISOs have problems on the new Acer? The ISOs are on NTFS drives on both systems. The Acer has double the RAM the Dell has.

?????

Ed_P

oops

"On my Windows 11 notebook these ISOs boot:"

should have been:

"On my old Dell Windows 11 notebook these ISOs boot:"

For some reason grub2 can't process the zstd file on the Acer. Any ideas??? BIOS, SSD, driver??