Ro replied on 28-Dec-06 07:23 PM
After a clean install of Vista I noticed there is a file in C: Drive called
Bootsect.bak and is visible even with hidden folders options set to not show.

What is this file and why was it created in a clean install? Also, is it
safe to delete it?

Colin Barnhorst replied on 28-Dec-06 08:28 PM
Depends on what you mean by a clean installation.  If you used the custom
install option then that did not result in a reformat of the disk.

.bak files can be deleted.
Ro replied on 28-Dec-06 10:47 PM
Thanks for the reply Colin. Good to know it’s safe to delete.

I've done many clean installs of Vista but this is the first time I've seen
this file. I may have forgotten but I'm pretty sure I selected to have the
drive formatted during install (or main partition deleted? - can't remember
which now).
Colin Barnhorst replied on 28-Dec-06 10:52 PM
I think the file is leftover from installation on a volume that had boot
code for XP or W2k.  In the event of an aborted installation Setup rolls
back to the legacy OS and would most likely rename the extension so that the
user could boot his old system.
Ro replied on 28-Dec-06 11:00 PM
So do you think something went wrong with the installation? Would there be
left-over files from previous XP or Vista installs still on the drive? Any
easy way to find out?

I'm getting no indication of anything amiss here as it's working ok; just
the bak file in question is all.
R. C. White, MVP replied on 28-Dec-06 11:00 PM
Hi, Rob.

Was WinXP (or Win2K) on your computer when you ran Vista Setup?  If so, you
probably also still have C:\NTLDR, C:\NTDETECT.COM and C:|Boot.ini, too.
These are the WinXP startup files that Vista's BCD (Boot Configuration Data)
will need for you to boot into the "previous version of Windows", if you
choose that option from the dual-boot opening menu of operating systems.
The file C:\BOOTSECT.BAK should be exactly 512 bytes; it is a copy of the
WinXP-style boot sector for the System Partition.  If you look at it in
Notepad, it looks like gibberish except for a few error messages at the end
and "MSDOS5.0" at the beginning.

R. C. White, CPA
San Marcos, TX
Microsoft Windows MVP
(Running Windows Mail 7.0 in Vista Ultimate x64)
Colin Barnhorst replied on 28-Dec-06 11:12 PM
No.  Setup will create the bak file during a normal installation.  It will
only need it if the installation fails.

Don't worry about it if you got a good install.
Ro replied on 28-Dec-06 11:12 PM
Windows XP SP2 was on there. But I booted from the Vista DVD and ran a clean
install (at least I'm pretty sure I did - formatted my HD).

The bak file in question was 8kb in size but I already deleted it so I
cannot see what was in it. Also, I don't have NTLDR, NTDETECT.COM or Boot.ini.
Ro replied on 28-Dec-06 11:24 PM
Thanks Colin.

If you don't mind me asking one more silly question; during a clean install
I recall being presented with the options of Format drive and Delete
Partition (it's only one physical drive with one partition). Is it best to do
a Format, Delete or both?

I must have selected something I've not done before during this install
because, as mentioned, I've never seen this bootsect file before.
Colin Barnhorst replied on 29-Dec-06 12:29 AM
I always do a quick format if I am installing a fresh copy of Vista.  I only
delete partitions if I was having boot problems and just want to start
completely over.  Seeing a bootsec file is normal if the drive has
previously been the boot drive for XP.
Chad Harris replied on 29-Dec-06 10:29 AM
Bootsect.bak and boot.bak are backup files from the previous xp bootloader.
They are not neededed for Vista,   and they can be safely deleted.

Ro replied on 29-Dec-06 06:42 PM
Hi Chad,

I already deleted the file. I am now just curious; is this file created
normally after every clean install of Vista? I had XP installed before I ran
the clean install but I thought when I selected the Format option during
Vista setup I would be wiping clean my drive, no?

I'm wondering what I did different this time as I've installed Vista before
on this machine but never noticed this file.
Colin Barnhorst replied on 29-Dec-06 07:14 PM
We have answered this a few times.  It is there because a previous version
of Windows was there.  Vista does not automatically do a "clean" install.
It does a Custom install or an upgrade install.  A custom install does not
format the hard drive before installing Vista.  If you want a classic clean
install you have to format the drive before beginning the installation.  If
you do an upgrade of course you are not reformatting.  Vista will create a
bootsec.bak so that if the upgrade fails it can restore the bootablility of
your previous system.  Why are you having trouble with this?
R. C. White, MVP replied on 30-Dec-06 12:36 AM
Hi, Rob.

I'm not sure of all the details.  I'm a retired accountant, fer gosh sakes,
not a techie of any kind.  ;^}

But I think the answer involves the fact that the boot sector is NOT a file,
so it is not wiped out by a format.  It is the first physical sector of each
primary partition or logical drive and, therefore, outside the file system;
it is not in any folder, not even the Root.  Its contents are created during
installation of WinXP or some other operating system.  It holds instructions
for use during the very early stages of booting, before the system even
knows how to handle partitions and directories.  MS-DOS and Win9x created a
boot sector that told the primitive system to look in the Root of the System
Partition for the files io.sys and msdos.sys.  WinNT4 through WinXP wrote
the boot sector to look there for the file NTLDR (no extension).  I haven't
read Vista's boot sector yet, but I suspect that it looks in the Root of the
System Partition for the file bootmgr (no extension) and the folder \Boot.

When Vista Setup runs, it reads the boot sector and, if it finds a previous
version, copies it into a new file in the Root of the System Partition
(\BOOTSECT.BAK) for safekeeping until it is needed to boot the previous
operating system.  If you create a dual-boot system, then each time you
reboot, the Vista system starts and gets to the operating system menu.  If
you choose Vista, it continues through the BCD process.  If you choose the
previous version of Windows, then BCD steps back out of the way and loads
BOOTSECT.BAK, which finds NTLDR and presents the WinXP-style menu from

So, yes, if you do not intend to dual-boot to a previous Windows, then you
can safely delete BOOTSECT.BAK, as well as NTLDR, NTDETECT.COM and Boot.ini,
if they still exist on your computer.

This may not be exactly correct.  I hope Chad or Colin or some other techie
can clarify or correct any goofs I've made.

R. C. White, CPA
San Marcos, TX
Microsoft Windows MVP
(Running Windows Mail 7.0 in Vista Ultimate x64)
Ro replied on 30-Dec-06 02:04 AM
Sorry Colin; didn't mean for this to aggravate you or anything. I appreciated
your responses.

I guess I was hung up on the fact that during the custom install that I did
I was presented with a FORMAT Drive option and thought that actually meant
led me to believe that it shouldn't matter what was there before (XP or
whatever else), it shouldn't leave the file in question after the install.

Anyhow it's not a big deal. Thanks again.
Ro replied on 30-Dec-06 02:06 AM
Thank you for the response R.C. It somewhat makes more sense now. Cheers.
Colin Barnhorst replied on 30-Dec-06 04:22 PM
Vista does not necessarily format the partition.  Custom install is not a
classic clean install.  To do a full format before installing one has to use
the Format tool in the Advanced Options when booting with the dvd.  If
running from the legacy desktop this is not possible.
Mark Severso replied on 04-Jan-07 10:31 AM
I have two has XP on it and the other...Vista.  For both I deleted
previous partitions and did the full format for XP and the format option for
Vista. I choose which os i want to boot into when I start the computer. Why
am I seeing bootsec.bak file in my XP hdd? Is it safe to delete?

Mark Severson
Windows 7 - NVM...i just read to keep my dual boot option...
Asked By Mark Severso on 04-Jan-07 10:55 AM
NVM...i just read farther...

so to keep my dual boot option...looks like i cant delete it.
Eddy Nielsen replied on 17-Jun-07 02:23 PM
I have also installed a clean vista. And also got these Bak file on 8 kb. Maybe this bak file could help me????

I got a serious problem, I have all my pic,(even from holiday) music, movie, and a lot of more stuff in the shared folder on drive D:. And then i format the Drive C: and installed a clean copy of vista. Then When I was finished I found out that theese shared folder on drive D: also got a clean copy. So i might think they have got a new direction, and now theese Shared folders are empty. I have tried to use some recovery programs and other oppotunities but nothing found. And also if i type D:tree or dir in cmd nothing showed. But my harddrive space is that much filed like before i copy a fresh clean Vista. I think that theese shared folders on drive D: got some new path. Plz some maybe could be nice to reply this??