BurnAware (
https://burnaware.com/ ) can make
bootable ISOs from folders. This means that first you must extract the files/folders of the input ISO to a folder.
BurnAware is free and said to be portable.
MGISO mentioned in the thread
viewtopic.php?t=3858 is available on the archive.org.
The web site is mirrored at:
https://web.archive.org/web/20130523174 ... /mgiso.htm
MGISO is free and portable.
I could start it on Win10 (64) and WinXP (32)
I tried it a dozen times on Win10 (64) and WinXP (32) but I got it to work only ONE time,and it was on Win10.
I believe the issue is with the string of switches passed to mkisofs.
If I had to deal with this problem, I would
1 - First extract the files/folders of the input ISO to a "MyIsoFolder"
2 - Do whatever needs to be done with the content of the folder
3 - Rebuild the ISO using AnyBurn or BurnAware and make sure you are using the BOOTABLE option
4 - You may want to verify that your "rebuilt" ISO is bootable --> Read
https://www.intowindows.com/how-to-chec ... -bootable/
I personally prefer MagicISO and the free / trial version is good enough to test the "bootability" of an ISO.