This article explains the problem of IndexError that you may face while installing ESXi 7.0. This error may be seen in multiple circumstances. Of the multiple possible scenarios, I faced it when I was trying to re-install ESXi on one of my servers.
The following setup was used:
- Dell PowerEdge R730 with 8 SSD Installed.
- For these hard disks, I configured RAID1 (HD1, HD2) for ESXi installation and RAID5 (HD3 to HD8) for my VMs.
- So, in total, I had two RAIDs configured which means I was able to see 2 datastores in ESXi storage TAB.

This server was running well until I rebooted my server and tried to clear RAID configurations and re-install ESXi 7. The following steps were followed:
- Rebooted Server, Pressed F2 to enter into System Setup.
- Cleared RAID Configurations and re-configured RAID.
- Attached Bootable USB with a server that had ESXi installable files.
- Rebooted the Server again and pressed F11 to enter into Boot Manager to boot my server from bootable USB.
Symptoms
The whole process worked well, and the installation started. However, when the required disk was selected to install ESXi, an unexpected error occurred.


This issue was faced because the boot disk had data from the previous installation, and it was not properly formatted. Even deleting and re-configuring RAIDs did not work in this case.
Resolution
To resolve this issue, navigate to System Setup / BIOS and Initialized RAIDs or virtual disks. When performing “full initialization” on virtual disks/RAIDs, it will overwrite all blocks and removes any data that previously existed on virtual disks. It is like formatting the hard disk to remove everything on it.

To perform “full initialization”, use the option “Slow Initialize” from the drop-down menu.
After the initialization process was completed, the server was rebooted to boot it from USB and the installation was completed successfully.
The Upshot
Of the many possible causes and solutions available for IndexError: list index out of range, one solution is to make sure that there is no data left on your boot disk and hard disks are properly formatted or initialized.
Excellent…
Just open console on tty/1, login as root (no password), use partedUtil to delete the partitions and press enter to restart the installation. 1 minute, no reboot, no complete deletion.