This error occurs when either of the below given conditions become true:
The Boot\BCD file present on the active partition is missing or damaged. .
The Windows Boot Manager (Bootmgr) entry is absent from the Boot Configuration Data (BCD) store.
Resolving this error requires the step by step following of the below given method
nsert the Windows installation disc in your computer disc drive
Select all the details that you are prompted to enter and click Next
Click Repair your computer and select the operating system you want to repair and click on it
Click Startup Repair
If the above given method does not resolve your problem due to any reason, you may try other methods as well, such as Rebuilding the BCD store using Bootrec.exe tool, or manually by using the Bcdedit.exe tool.

