How to change bootmgr file name to oldbootmgr

I am wondering how to change the bootmgr file name to oldbootmgr. This is part of an exercise to intentionally crash window on boot up. Can anybody help me with this?

Thanks!!

You'd have to do it from WinRE using Command Line or accessing the file to delete using Copy & Paste - in Windows Recovery Console, or using a boot disk like Hirens which is not supported here. Save a Win7 backup image first in case it becomes irreparable.

All boot repair commands are automated in Win7 Startup Repair. It will actually rewrite the Win7 boot files to the Active partition when run Startup Repair - Run up to 3 Separate Times.

Perhaps we can save you the trouble by asking your questions here where we have dealt with countless thousands of these since before Win7 was even released.

@OP, you can do that using a linux distribution like Ubuntu (Home | Ubuntu). Make a bootable pendrive and boot using it. After you reach the Ubuntu desktop, open up file explorer (or 'computer', whatever it's called) from menus at top, navigate to the required location and rename the file you want. Now restart to see an unbootable Windows!

Just make hidden and system files visible in explorer (or any other file manager you use) and rename it, it works directly, only showing an UAC prompt and a lot of warnings since it's a critical system file, but it lets you rename afterwards, that's simple as it's not in use once the system boots.

The only problem you can have is that if you're using the hidden 100MB partition, bootmgr is located there instead, so you have to make that visible and assign a drive letter beforehand or use an external OS.

In any case, if you don't rename it back, Windows will no longer boot, I guess not even the F8 menu can show, but repairing it is a matter of renaming it back somehow.

I would like to thank you all for your replies. Two of us had the one particular problem in the class where the instructors were not even able to figure it out.

After doing the correct alterations to the Folder options ofnow showing hidden files and unchecking the operating system files, bootmgr did not show up in the root of the C drive. It was a truly frustrating experience. Have any of you more seasoned experts ever come across this?

Did you have another partiiton marked System such as the 100mb System reserved partition which the Windows 7 installer creates for the System boot files? The file should be on the partition marked System.