How to fix error: reboot and select proper boot device or insert?

Question

Hard disks

There was an old disk - I bought a new one and installed Windows on the New one (at the installation stage it was divided into 2 partitions at once - for Windows and for other files). The old one thought to use it as a flash drive. But now I wanted to turn it off, turned it off and turned on the PC - but at the boot stage I got the following error: reboot and select proper boot device or insert boot media in selected boot device and press a key. How can you painlessly turn off the old hard drive completely, but so as not to re-install Windows again?

Answer 1

The MBR of the new disk is empty, the bootloader remains on the old one. You can try to restore (by downloading the recovery program from a USB flash drive) or boot from the old one and install the bootloader on the new one.