Before mounting the ISO, execute the following (Linux/Mac example):
# Download the ISO (example from archive.org)
wget https://archive.org/download/xenserver-7-6/XenServer-7.6.0-install-cd.iso
Before you burn the ISO to a USB drive or mount it in your out-of-band management interface (iDRAC/iLO), ensure your hardware is compatible. xenserver 7.6 iso download
Solution: XenServer 7.6 only supports Legacy BIOS boot mode. Change your server’s firmware from UEFI to BIOS/CSM mode. Before mounting the ISO, execute the following (Linux/Mac
Solution: Citrix purges old EOL files quarterly. Try the Wayback Machine (archive.org) for community mirrors, but verify checksums. Better yet, use XCP-ng 7.6 instead. Before mounting the ISO