Login screen failure

Hi all,

Since this afternoon, my desktop XP computer won't start. I come to the
login screen, but after typing my password + Enter, it hangs. No mouse
pointer and no marker. It doesn't even bother to check if the password
is right. When trying the "Guest" or "Turn off computer" buttons, it
also hangs with an eternal hourglass.

It starts OK in safe mode, and no files are lost. How can I see what's
wrong?

Gustaf

What happened 'this afternoon' that might be causing this problem?

A computer can fail to start for an unlimited number of reasons. Without
any direction or clues from you, we're playing a guessing game.

Here's my first guess: If the computer starts and runs fine in Safe
Mode, something that normally loads with the computer may be causing a
problem.

If Windows knows anything about it, the information is in Event Viewer.

Otherwise, suspect malware.

Failing that:

"How to perform advanced clean-boot troubleshooting in Windows XP"
http://support.microsoft.com/kb/316434

Thanks Leonard,

I'm clueless myself, since I haven't done any changes. I turned it on
this morning, and it worked fine as usual. Then after turning it off for
a while, it wouldn't start. There were no hardware or software changes
in between.

I noticed there was a Windows update waiting to be installed last time I
turned it off. So I turned it on in safe mode and uninstalled the latest
update (KB969947), but it didn't help.

Diagnosing Windows XP startup problems isn't all about guesswork, is it?
There must be some way of having the system tell you what's wrong.

you might try to open a
task manager there or
a shift tab to see if you
get any responsiveness.

also you can also try to boot
into safe mode and see
if you can access the system.

[youmadethisnecessary]

Nov.11,2009 Lastest win xp update KB969947 caused blue screen fatal system error c000021a preventing my computer to boot up.

The procedure below worked for me,my computer is backup and running.
***********************************************
Uninstalling update KB969947 using Recovery Console

Boot into the Windows XP Recovery Console using the Windows XP CD-ROM or using the startup option (if available). See article How to install and use the Recovery Console in Windows XP for more information.

Type in the password for your installation of Windows XP, and press Enter.

When you see the C:\Windows Prompt, type this command:

DIR $*

This lists all the folder starting with the letter $. All the $NtUninstall.... folders are now displayed. $NtUninstall folders are nothing but the Hotfix backup folders, which contains the original version of the system files, before the hotfix was installed.

Note down the Hotfix numbers matching the date you installed the problematic Hotfix(es). Spot the Hotfix that you want to remove, and change to that directory by typing this:

CHDIR $NtUninstallKBnnnnnn$\spuninst

Example:

CHDIR $NtUninstallKB873333$\spuninst

Once you're in that folder, you'll need to execute the spuninst.txt which contains DOS commands, similar to a .BAT file. The command instructions in this spuninst.txt file will actually copy the original system files to their respective folders. To run the spuninst.txt file, type this:

BATCH spuninst.txt

The hotfix will be uninstalled. Restart, and see if the problem is resolved. If Windows loads normally, open Add/Remove Programs and completely uninstall that particular hotfix. This ensures that the additional files, Add/Remove entries and other registry keys added by the Hotfix are removed completely.

If Windows does not load, load Recovery Console again and then follow the above procedure to remove the additional Hotfixes one at a time, to isolate the problem. If you install multiple Hotfixes in a single session, it's difficult to point out which of the installed Hotfixes is preventing Windows XP from loading. Hence you need to troubleshoot it on a trial and error basis, using Recovery Console.
http://windowsxp.mvps.org/spuninst.htm

If suggestions include words like try, maybe, might be, could be,
etc., that might be construed as guesswork.

Provide more information about your system, run some scans for
malicious software and post relevant events around the time of the
issue:

Click Start, Run and in the box enter:

msinfo32

Click OK, and when the System Summary info appears, click Edit, Select
All, Copy and then paste
the information back here.

There will be some personal information (like System Name and User
Name), and whatever appears to
be private information to you, just delete from the pasted
information.

This will minimize back and forth Q&A and eliminate guesswork and
assumptions.

Perform some scans for malicious software first, then fix any
remaining issues:

Download, install, update and do a full scan with these free malware
detection programs:

Malwarebytes (MBAM): http://malwarebytes.org/
SUPERAntiSpyware: (SAS): http://www.superantispyware.com/

They can be uninstalled later if desired.

To see the Event Viewer logs, click Start, Settings, Control Panel,
Administrative Tools, Event Viewer.

A shortcut to Event Viewer is to click Start, Run and in the box
enter:

%SystemRoot%\system32\eventvwr.msc /s

Click OK to launch the Event Viewer.

If you do find interesting events in the Event Viewer that are at the
date/time of your issue, here is an efficient method to post the
information.

The most interesting logs are usually the Application and System.
Some logs may be almost or completely empty.
Not every event it a problem, some are informational messages that
things are working okay and some are warnings.

Each event is sorted by Date and Time. Errors will have red Xs,
Warnings will have yellow !s.
Information messages have white is. Not every Error or Warning event
means there is a serious issue.
Some are excusable at startup time when Windows is booting. Try to
find just the events at the date
and time around your problem. No event should defy explanation.

If you double click an event, it will open a Properties windows with
more information. On the right are
black up and down arrow buttons to scroll through the open events. The
third button that looks like
two pages on top of each other is used to copy the event details to
your Windows clipboard.

When you find an interesting event that occurred around the time of
your issue, click the third button
under the up and down arrows to copy the details and then you can
paste the details (right click, Paste
or CTRL-V) the detail text back here for analysis.

To get a fresh start on any Event Viewer log, you can choose to clear
the log (backing up the log is offered),
then reproduce your issue, then look at just the events around the
time of your issue.

Do any of these problem systems happen to be Dell computers, AMD
chipset with/or an ATI Radeon video card?

Several of my xp machines fail (freeze after login) after installing KB969947.

I found this way to restore system easy and fast:

1) boot system in safe mode
2) run system restore from start menu (all programs-->accessories-->system
tools-->system restore)
3) choose closest date before installing last updates (look for system
checkpoint) and restore system.

System will reboot in normal mode without security update installed.

Yes. I has happened on some of my DELL Optiplex 755 machines (intel
quad-core's), not all of them though.

A compelling and versatile solution (according to Dell). Why did I
know that... Any 745s in the mix?

Since you have the problem on several machines, they all sound
afflicted with the same issue.

I suspect the problem is that the video drivers need to be updated and
the ones from the Dell site may not work unless they updated them in
the last day, so you should figure out what your video device is and
go to their WWW site and get them.

If the video type is ATI Radeon (if not, what is it), you should
uninstall KB969947, reboot, download and install the latest ATI Radeon
drivers from here:

http://game.amd.com/us-en/drivers_ca...=xp/radeonx-xp

Whatever the video type, make sure you have the latest drivers.

Reboot, reapply KB969947.

Reboot, test.

Or, you could just uninstall KB969947 and not have the critical update.