macOS High Sierra could not be installed: An error occurred while verifying firmware.

Hello.

I have a problem while installing macOS High Sierra on my new iMac.

Here is the picture with an error that occurs in the middle of the process:

I have tried several approaches to resolve it but all of them were unsuccessfully, every time I see the same error:

• Install update from Apple Store
• Install update from Apple Store in Recovery Mode
• Install update using USB and bootable flash card
• Clean SSD and install update from USB

I have cleaned SSD and installed "last available" version using Recovery Mode (cmd+shift+R) and it is Sierra 10.12.6

Here is an information about iMac:

• macOS Sierra 10.12.6
• iMac (Retina 5K, 27-inch, 2017)
• Processor - 3.4 GHz Intel Core i5
• Memory - 16 GB 2400 MHz DDR4
• Startup Disk - Macintosh HD
• Graphics - Radeon Pro 570 4096MB
• Storage - 225.38 GB available of 250.14 GB