|I assume you are trying to flash the BIOS? - if yes, telling us that's what you are trying to do would have been helpful. |
It's the type of boot disc you are using (Hiren's Boot CD). It's loading the himem.sys & EMM386.exe DOS memory manager files into memory. These are loaded into memory via two startup files, AUTOEXEC.BAT & CONFIG.SYS
You need to use different boot media which doesn't load the memory manager files.
The "Driver Free Disk For BIOS Flashing" from bootdisk.com is what you need:
Click the "About" link next to that item, it will explain what to do if your PC has no floppy drive.