FATAL : No Bootable medium found , after adding disk to VBOX Virtual Machine

While working on adding disk to my VBOX virtual machine, i come across minor issue, thought to share with community.

FATAL : No Bootable medium found ! System halted

Issue was caused by adding a disk to virtual machine with lower port number then existing (only) disk ,which had operating system installed.

 Checking Storage property of machine revealed the new disk "Linux0001-02.vdi" which was just added been assigned with SATA Port 0 ID, and when machine restated it look for this disk for operating system and there was none as i just added this disk.

To fix the issue, assign a higher number to new added disk, to move this disk down the order.

Click Settings>>Storage>> click on diskname>> change Hard disk Port number from drop down list >> click ok.

Bow we can see new disk is appearing 2nd in the list , making my old disk to be first one to be read.

Try starting the VM again and here we go, it found the operating system it was looking for.