This has happened I have no idea HOW many times....someone changes out their bootscreen without backing it up, or taking the time to ensure they had a recovery plan, and then the bootscreen doesn't work. Or any number of possible situations can happen (bootscreen put in wrong directory, etc.) and you cannot boot up your computer any longer. Well, that's no good at all. Luckily, a great member at ThemXP.org named jrzycrim wrote up a comprehensive tutorial on how to restore your original bootscreen should something go haywire.

Be Advised!! I have read through this tutorial and to the best of my knowledge, as far as I can tell, it is solid. However, bfarber.com cannot take any responsibility regarding bootscreen issues (including problems that may occur by following this tutorial) under ANY circumstances. This is provided as a guide to help assist you in restoring your original bootscreen should your XP become unbootable. Take it at face value.

With that said...


Restoring your original ntoskrnl.exe (bootscreen) file.

See this link about making a recovery Floppy Disk: http://www.themexp.org/forums/viewtopic.php?t=7397

The most common reason your computer will not boot after installing a new bootscreen is because the ntoskrnl.exe file you installed was the wrong version for your system. There are several different versions for both pre-SP1 and SP1 editions. A bootscreen you downloaded might be labled for sp1 but this does not mean it will necessarily work if you have SP1 installed. You might have 5.1.2600.1106 and the one you have downloaded may be version 5.1.2600.1151 or 5.1.2600.1224.

The only sure way is to check the version which is on your system. The easiest way is to navigate to your System32 folder, usually C:\Windows\System32, find the ntoskrnl.exe file, and let your mouse pointer hover over the icon until the tool tip is displayed. You can also right click on the file and select properties, then select the version tab.

Do the same to the ntoskrnl.exe file you downloaded and compare. If they aren't the same, don't use it!!!


99% of the time it is not necessary to re-install Windows XP if you have installed the wrong version or a corrupt ntoskrnl.exe file. A copy of your original ntoskrnl.exe file should be stored in the C:\Windows\drivercache\i386\ directory unless it has been deleted or copied over. Let's hope this isn't the case. It's most likely there, however. The trick is getting the computer to boot and restore the original file.

First thing we need to do is to try and boot into safe mode with the command prompt. Sometimes it is possible to boot into safe mode with a bad ntoskrnl. If you cannot then you will have to use the recovery console which is not hard, just takes a few minutes longer.

[Safe mode method]

1) Reboot/turn on your computer (remove any floppies or CDs from the drives)

2) Press F8 during the OEM logo screen or blank screen just before the bootscreen is displayed. This will bring up a menu of different boot options. (You might have to hit the F8 key more than once to get the menu)

3) Select 'Safe mode with command prompt'

4) If an administrator password was set during the original installation, then you will be prompted to enter it.

*If you were unable to boot into safe mode, then skip to the [recovery console method]

5) Once at the command prompt, type the following commands, hitting enter after each line:

You should see something similiar to this:


The last line is what we are interested in.

*The command line editor does not wrap the text so make sure you move the cursor all the way to the right on the last line.

If you used a program such as booteditor or a bootscreen randomizer, then most likely your original ntoskrnl.exe file is still intact. These types of programs just place the new ntoskrnl file under a unique name such as newkrnl.exe and edit the boot.ini file to point to that file instead of overwriting the original ntoskrnl.exe.

6) Delete all the text 'after' /fastdetect if there is any, and then hit [ALT],[F],[X], (one after the other, not at the same time) and then select yes to save and exit. If you accidently messed up the text in the boot.ini file, then just [ALT],[F],[X] and select no. Then type edit boot.ini again. If necessary, type: copy boot.bak boot.ini, just in case you accidently saved the bad text or whatever.

Reset the file attributes:


If /kernel=bootprogram.exe was used, and you deleted that text and saved the boot.ini file, it should be okay to reboot at this point. If not, or if after rebooting you still have a problem, then continue on to the next steps.

If the /kernel= switch was not present in the boot.ini file or you are still experiencing problems booting up, then the original ntoskrnl.exe file is corrupt or the wrong version. Continue on:

7) Follow steps 1-4 to return back to the command prompt, and then type in the following commands:



When prompted to overwrite the old file, select yes (y). You should see the message, '1 file(s) copied'.

If you got a file not found or other error, then make certain that you are in the system32 directory and check the spelling of the commands.

8) If the file was copied sucessfully, then reboot normally and all should be okay. If you are still having a problem, then go to the last section of this text.

[Recovery console method]

If you are not able to boot into Safe Mode, then you will have to use the recovery console on the XP installation disk. It's not any more difficult, it just takes a little longer to load.

1) Put in your Windows XP installation CD and reboot.

2) If prompted, press any key to boot from the CD. (NOTE...if your PC doesn't try to boot from the CD, you will likely have to edit your BIOS to change the boot order. While this is beyond the comprehension of this tutorial, in general, immediately after you reboot, hit ESC or F1 or F2 and your BIOS will display, wherein you can tell your computer what devices to boot from first...ensure CD Rom drive is selected as the first boot device)

3) When the first screen appears, do not enter any choices yet, just let Windows load from the CD. This will take a couple minutes. Don't worry, it is not re-installing XP.

4) You will be presented with a list of three options after Windows Setup loads. Select the second option: 'Press R to repair a windows installation using the recovery console'. This is not the same as a repair installation.

5) A list of available operating systems will be presented. If you have just one (Windows XP professional for example) then type 1 and enter. If you have multiple operating systems, select the one that is having the boot problem. If an administrator password was set during the original installation, enter it when prompted.

6) From the command prompt, type this:


It will start scanning your hard drive for available operating systems. It will take a minute.

It will then display a list of operating systems and prompt you for different responses...


Type y and enter.

Type Windows XP and enter (Actually, whatever you want to put here is fine. Whatever you choose will be displayed on a menu when you reboot.)


Type "/fastdetect" without the quotes and hit enter.

(7) The next step is restoring the original ntoskrnl.exe.

This step is just a precaution in case the ntoskrnl is the wrong version or corrupt. Might as well do it while you are already in the recovery console. It's a bit of a pain loading the console.

Type these commands:

CODE

systemroot
cd system32
copy "..\driver cache\i386\ntoskrnl.exe"

When prompted to overwrite the old file, select yes (y). You should see the message, '1 file(s) copied'.

(8) Reboot

A boot menu will be displayed. Select the OS you typed at the Load identifer Prompt when restoring the boot.ini.
Things should boot up normally.

If it still doesn't boot, then see [When all else fails] at the end.

If you don't want to see the boot menu evertime you boot up, then you will have to edit the boot.ini manually after windows starts up normally.

Go to the start menu, select run, enter CMD.

You should be at a command prompt.

Type the following commands:

CODE

cd c:\
attrib -r -s -h boot.ini
copy boot.ini boot.bak
notepad boot.ini

In notepad you will see something like this:

CODE

[boot loader]timeout=30
default=multi(0)disk(0)rdisk(0)partition(2)\WINDOWS
[operating systems]
multi(0)disk(0)rdisk(0)partition(2)\WINDOWS="Microsoft Windows XP Professional" /fastdetect
multi(0)disk(0)rdisk(0)partition(2)\WINDOWS="Microsoft Windows XP Professional" /fastdetect /kernel=newkrnl.exe

Maximize the note pad window so the single lines don't wrap and make it confusing.

Under [operating systems], delete any line that contain the /kernel switch. Leave the partition information as it is. This will be different depending on what partition your OS is setup. Mine is on 2. Yours may be on 1 or 3. The main goal is to just have one line for "Windows XP" pro or home, without the /kernel switch telling the bootldr to use a different, possibly faulty kernel.

If you have multiple operating systems, (ie. Windows 2000 or 98 or any other) then leave those entries alone. Just make sure that there is only one entry for WindowsXP with nothing after /fastdetect.

You should now have something like this:

CODE

[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(2)\WINDOWS
[operating systems]
multi(0)disk(0)rdisk(0)partition(2)\WINDOWS="Microsoft Windows XP Professional" /fastdetect

Now save your changes and exit notepad. At the command prompt, type:

CODE

attrib +r +s +h boot.ini

This turns back on the read only, hidden, and system attributes of the file. This is how it is by default.



[When all else fails]

If you have tried all the above steps and still experience a problem booting your system, then a re-install may be your only hope. I know what a pain that can be. Getting everything set up just the way you want takes a long time if you don't have a current backup or image of your hard drive. It's possible to extract the original ntoskrnl.exe file from the installation CD, but 9 times out of ten this won't work. If you have updated to SP1 then the original file on the CD is not the same version and will not work. If you have a installation cd with SP1 slip-streamed, then the chances are better but even then, post SP1 hotfixes may have updated the ntoskrnl files and you are back to square one. If you have a friend that has XP, you might be able to copy the file from his computer, but unless you know what version you need, then this may not work either. If you are stuck re-installing your OS, then I would suggest perfroming a 'Repair install'. It takes just as long as a clean install but it leaves your installed applications intact. However, you will have to re-install SP1 and all the hotfixes and updates. Good Luck!

[[Last edited by jrzycrim on Nov 21, 2003 2:59 pm; edited 16 times in total]]