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Get the fix for the "<strong>Failed to find OS Loader</strong>" error for <strong>Windows Vista, Windows 7, Windows 8 </strong>and<strong> Windows 8.1</strong>
<h2>About "Failed to find OS Loader"</h2>
[kbintro]
<h3>Synopsis</h3>
The error "Boot manager failed to find OS loader" is displayed when Startup Repair fails to correct problems with a non-booting PC.

In particular, this message indicates that Startup Repair was unable to find the correct BOOTMGR bootloader at the expected location(s). While the usual fix for a missing bootloader is to run Startup Repair, in this case, Startup Repair is unable to correct the problem for one or more reasons.
<h3>Symptom 1: Startup repair fails with message "Boot manager failed to find OS loader"</h3>
When attempting to use the automated repair feature of Startup Repair, it attempts to repair your PC but fails. Clicking to view the contents of Startup Repair's "Diagnosis and repair details" reveals the error to be "Boot manager failed to find OS loader" with one or more failed repair attempts. Example message:

The full text:
<pre>Root cause found:
---------------------------
Boot manager failed to find OS loader.

Repair action: File repair
Result: Failed. Error code =  0x3
Time taken = 1529 ms

Repair action: Boot configuration data store repair
Result: Failed. Error code =  0x2
Time taken = 0 ms</pre>
<h2>Causes of this Error</h2>
This error has been known to occur as a result of one or more of the following:
<h3>Cause 1: Corrupt boot volume</h3>
Corruption of the boot partition on a Windows PC can cause this error to present.

The filesystem on the boot partition can become corrupted as a result of an unsafe shutdown, sudden power loss, unsafe removal of local and/or external drives, or physical damage to your computer's hard disk, amongst others.

Corruption of the boot partition is known to occur on both NTFS and FAT32 partitions.
<h3>Cause 2: Bootloader was deleted</h3>
Windows Vista, Windows 7, Windows 8 and Windows 8.1 use the new BOOTMGR bootloader.

On Windows Vista, BOOTMGR is found in the root partition of your Windows installation drive (normally drive C:\).

On Windows 7 and above, BOOTMGR is typically located on a separate 100 MiB NTFS partition created at the beginning of your drive during setup. This file can be deleted due to a failed Windows Automatic Update installation, a failed attempt at upgrading the OS, or by viruses and other malware.
<h3>Cause 3: Hard disk was removed</h3>
If your computer had more than one hard disk, and you have removed or replaced one or more of these disks, this error can occur.

If the disk that was removed or replaced was the first boot device in the BIOS, the boot files would have been installed to this drive, <em>even if Windows was on a different physical disk</em>.

It's important to be sure that the boot files <a href="https://neosmart.net/wiki/easybcd/basics/changing-the-boot-partition/">have been moved to a different drive</a> before replacing a boot disk in your PC.
<h2>Fix Cannot find OS Loader on Windows</h2>
<h3>Fix #1: Use Easy Recovery Essentials</h3>
[easyre error="Failed to find OS Loader" guaranteed="true" bootscreen="xp-vista-7-8"]
<h3>Fix #2: Use the System File Checker</h3>
[setupcd]

[partial name="partial_sfc"]
<h3>Fix #3: Manually rebuild the BCD, MBR, and bootsector</h3>
[partial name="partial_rebuild_bcd"]
<h2>More Information</h2>
<h3>Linked Entries</h3>
<ul>
 	<li><a href="https://neosmart.net/wiki/bootrec/">bootrec</a></li>
</ul>
[partial name="partial_moreinfo" versions="vista,7,8,server2008,server2012"]