Fixing the "BOOTMGR is Missing" Error in Windows 7 If you’ve powered on your computer only to be met with a black screen and the dreaded message you aren’t alone. This is one of the most common startup issues for Windows 7 users.
Important: Startup Repair may need to be run to fix all issues. windows 7 bootmgr download
Restart the computer and enter the BIOS/Boot Menu (usually F2, F10, Esc, or Del) to set the USB/DVD as the primary boot device. When prompted, press any key to boot from the media. Select your language and keyboard layout. Click "Repair your computer" (do not click "Install Now"). Fixing the "BOOTMGR is Missing" Error in Windows
This is the most effective way to "download" or restore the BOOTMGR file from your existing system files. Restart the computer and enter the BIOS/Boot Menu
This removes the corrupt BCD and creates a fresh one.