Corrupt file at startup, can not start up Win 7- resolved using a repair installation

I get "Problem Signature 04: 21200284" as of this morning after running the new Windows 7 64 bit Security Update.. Pretty pissed at this point.

Tried all the steps, however :

bootrec.exe  /RebuildBcd   can not find any Window 7 installations?

Mark.

Thanks for the instructions - I would just like to clarify something. I put the original Windows disk in and have gotten to the DOS prompt. It shows as Z:/, which I am assuming is the drive with the Windows disk. Got all the way to the end and nothing changed

• still can't boot. My problems are :

D:\Windows\system32\drivers\nvstor.sys is corrupt and

D:\storport.sys is corrupt

Do I have to change the drive to D:/ to make the changes in the corrupt file on the harddrive? 

Thanks for any help you can provide.

Carol

Updated instructions:

How to repair and reboot to Windows 7:

a) Insert the Windows 7 System Repair DVD or Installation DVD and reboot.

If you do not have access to either disc: Windows 7:  ISO download with SP1 included

http://techdows.com/2011/07/download-windows-7-integrated-with-sp1-iso-official-direct-download-links.html

Create a Bootable Windows 7 DVD using the .ISO file

Burning a Windows 7 ISO File on a DVD

http://support.microsoft.com/default.aspx/kb/977640

b) Select the correct keyboard input method and click ‘Next’.

Note: If you are using the Windows7 Install DVD then at the 'Install Now' prompt (Do not pick the Install Now option) instead choose the 'Repair your computer' option located in the lower left of the display.

c) The System Repair tool will search for a valid operating system and will report that “Windows found problems with your computer’s startup options. Do you want to apply repairs and restart your computer?”

d) Click ‘Repair and restart’ and reboot again to the Windows 7 System Repair environment.

e) Click ‘Next’ at the keyboard selection prompt and when the ‘System Recovery Options’ screen appears verify that the “Use recovery tools that can help fix problems starting Windows” is selected.

Note: On a Dual Boot system there may be only one operating system listed if you have removed one of the two versions of Windows 7. Click the ‘Next’ button.

f) Now from the menu list select the ‘Command Prompt’ option.

g) At the DOS prompt type the following three commands:

bootrec.exe  /fixmbr

bootrec.exe  /fixboot (may return an 'Eliment not found' message)

bootrec.exe  /RebuildBcd

h) Close the command prompt window and click the ‘Startup Repair’ option.

i) The repair process may take some time, so wait until the process completes at which point you will see two messages “Windows cannot repair this computer automatically” and “Startup Repair cannot repair this computer automatically”.

These messages are the result of the radical changes made by removing the other drive. Ignore the Send/Don’t send options.

Note: Please perform step j as detailed below, startup repair must be run multiple times (at least 3 times).

J) Close this message window by clicking on the X in the upper right corner of the Send/Don’t send window. Next click on the ‘View advanced options for system recovery and support’ option and from the main menu once again click ‘Startup Repair’. This time the repair process may only that a few seconds and when prompted “Startup Repair could not detect a problem”, click ‘Finish’  and run the ‘Startup Repair’ option one more time, click ‘Finish’, and then remove the System Repair DVD and click ‘Restart’.  Reboot the computer.

J W Stuart: http://www.pagestart.com

Thanks for still being available to answer questions about this.

Unfortunately my desktop (running Win7 64) started freezing up at startup on the 16th and I tried your instructions using the original Install DVD but it froze immediately after selecting "Repair Your Computer" - this is slightly longer into the process than has been in the last 4 attempts prior to trying the DVD.

I was able to get through system diagnostics after it one of the initial hard resets and it didn't find any other problems with the system (sorry, I've forgotten the exact verbiage and can't get it to run again) but I did write down the error info it did provide:

"* Root Cause: Unspecified system changes might have caused the problem."

Repair Action: System Files Integrity Check and Repair

       Result: Failed

       Error Code 0x490

       Time Taken: 1282187 ms

Later I tried again and selected System Restore but upon first reboot it froze at the Windows symbol.

It has on the last 2 attempts almost acted like there was a just a nasty lag in the startup processes as several minutes after my mouse stopped it jumped to another location but it never made it past that.

What do I do? I don't have this machine backed up so I can't afford to just flatten and run a clean install. (it was my backup which became my only after my laptop power supply started shorting) I have a brand new machine and a brand new external HD that made it as far as out of the box prior to this mess.

thx

d