SG300 Firmware Upgrade Copy: Illegal software format

In this short article, we will discuss “SG300 Firmware Upgrade Copy: Illegal software format”. Please see How to enable Secure Boot on PC to install Windows 11, and How to enable or disable Secure Boot in Windows. When I had this error, some articles suggested that you need to install the upgrade the boot loader first. Before attempting the firmware upgrade. The Boot loader (.rfb file) can be found on the same zip folder as the firmware. This does not work in this case.

SG300 Firmware Upgrade
A firmware is software that is embedded on the router. This firmware is normally updated to include new features and enhancements to the device. All of our firmware upgrades are FREE.
Please see What are the Differences between UEFI and BIOS. Also, see how to update the BIOS on your Dell system, and a “Video on how to Fix the Boot Failed UEFI SCSI Device on HyperV“.
Solution to Illegal Software Format
The steps below fixed the issue(SG300 Firmware Upgrade). All that needs to be done to correct this issue is to perform an interim firmware upgrade to the previous version. Then upgrade form this version to the next, till it gets to the most recent one.
The switch flash file system was changed in 1.3.7.18
I hope you found this article useful on how to fix “SG300 Firmware Upgrade Copy: Illegal software format”. Please feel free to leave a comment below.