FATAL: No bootable medium found? System halted.

[Advice Pro]

I created a VDI for an ISO and I don't know what I did wrong in settings. In Settings > Storage, I had set the ISO at the IDE Controller. What do you think can be wrong?

[Perryg]

I really don't know what you are trying to do but try to mount the ISO to the virtual CD/DVD drive. Other than that you are going to need to better describe what it is you are trying to do.

[mikeinnyc]

try secondary not primary in your settings for your DVD