sounds like both hard disks were present when you installed windows, so some boot files could be still there, in the disc that you removed, perhaps a boot partition or a boot recovery partition, 100 or 500 megabytes partitions windows 8 or 10 uses, windows 7 too
that or you changed order of hard disks and uefi bios is complaining so, set the right disk to boot, the ssd in this case
if that doesn't work perhaps repair installation with the installation disc
if that doesn't work, reinstall windows, do backups of everything first