Windows 2000 boot looping

[gib]

After installing Avast I can't boot my W2K SP4 box normally.  It gets stuck in a boot - disk check loop.  I have to boot "Enable VGA mode", which cripples the video display.  Uninstalling Avast solves the problem.

My previous antiviral software was AVG 7.5, which I upgraded to AVG 8.0, which didn't work at all (wouldn't scan).  I uninstalled AVG 8.0 via Control Panel > Add/Remove Programs, no other antiviral or firewall software has been installed.

Any suggestions?

[DavidR]

We seem to be seeing more issues with AVG possibly not fully uninstalling.

AVG Remover, download tool from here, http://www.grisoft.com/ww.download-tools there is a 32bit and 64 bit windows version, ensure you use the correct one.

You could boot into safe mode and uninstall avast, then reboot and see if that at least gets you into the boot. Run the avg uninstall tool reboot and install avast.

[gib]

Thanks David.  I downloaded and ran the AVG remover.  It isn't clear that it found anything to remove.  In any case it didn't change anything.  I reinstalled Avast, rebooted and was stuck in the boot loop again.  The only way to escape is via "Enable VGA mode", which allowed me to boot up and uninstall Avast.

A "Safe mode" startup halts for ever at the point where the last line displayed is about starting the service for agp440.sys.  A google search on agp440.sys problems yields a confusing range of causes, implying that the failure may have no connection with this file.  It might be worth mentioning that the video card is an nVidia GeForce 4, Ti 4400, and the first time I installed Avast and booted (in VGA mode) the Hardware Manager told me that the display driver was not installed.  I had to reinstall from the CD.  Since then this odd loss of the driver has not occurred.

Another little thing that caught my attention in the bootup process is that there is a noticeable pause on the first screen at the last drive detection point "Detecting Secondary Slave"  (there is none).  Normally this goes in a fraction of a second, but with Avast installed it lingers for several seconds.  Could this be a clue?

By the way, the single drive in this machine is formatted (for historical reasons) as FAT32.  Could this be a problem?

[DavidR]

Well on my last system (XP Pro) I had two HDDs both formatted as FAT32 and no problems, so I doubt this was the problem.

I was more looking at elimination by using the avg uninstall tool.

As you say having to enable VGA mode would kill your graphics card driver and strange as it may seem the driver issue may have been co-incidental as if your driver went down that may have been why you got the enable VGA mode. Your re-installation of the driver seems to have got past that particular issue.

avast doesn't actually run in safe mode, so if you boot into safe mode avast shouldn't play any part in the other issues, re HDD, etc.

You say you only have one HDD, but do you have an optical drive sharing the same IDE cable as the HDD ?

[gib]

The Safe mode issue might be a red herring.  I can't remember whether I've ever tried to boot in safe mode before.
I'm at work now (the problem is on a home box) so I can't check the IDE cable issue (memory no use on things like this).  Come to think of it, I also need to check ability to boot in safe mode without Avast installed.  Currently the system is unprotected, except by the ADSL modem.

The video driver problem could be coincidental, but it seems to be a pretty big coincidence.  My main problem is not having much of a clue about what Windows 2000 does on bootup.  Linux is so transparent by comparison.

[DavidR]

You're not alone in not knowing much about win2k, well your practical knowledge is greater than mine, I have never used it at all.

[essexboy]

Read this http://support.microsoft.com/kb/324764

[gib]

Yes, I saw that.  It doesn't seem to be relevant, not in any obvious way, anyway.  I can boot successfully except when Avast is installed.  I have established that this is completely repeatable.

I have to correct one statement that I made previously.  I thought that the bootup was getting stuck at agp440.sys when booting in safe mode with Avast installed.  This was my mistake.  It takes a long time, but if I wait long enough the boot progresses beyond that point.  The boot loop problem is still there though - near the end of the boot sequence it reboots into the disk check stage again.

Without a doubt Avast is preventing my system from booting.

[gib]

Well on my last system (XP Pro) I had two HDDs both formatted as FAT32 and no problems, so I doubt this was the problem.

I was more looking at elimination by using the avg uninstall tool.

As you say having to enable VGA mode would kill your graphics card driver and strange as it may seem the driver issue may have been co-incidental as if your driver went down that may have been why you got the enable VGA mode. Your re-installation of the driver seems to have got past that particular issue.

avast doesn't actually run in safe mode, so if you boot into safe mode avast shouldn't play any part in the other issues, re HDD, etc.

You say you only have one HDD, but do you have an optical drive sharing the same IDE cable as the HDD ?

I have now found that contrary to my previous statement the boot process doesn't get stuck at agp440.sys, it just spends a long time there.  The boot still loops though, with Avast installed.
My CD drive and HDD are on separate cables.

[DavidR]

I'm not entirely sure I understand what this "The boot still loops though," or your original post "It gets stuck in a boot - disk check loop."

If you are talking about checking for hard disk errors, which is typically an indication of improper shutdown or actual errors on the HDD. Are you getting any hang-up when you shutdown ?

You could try Windows Start, Run, type cmd, this will give a command prompt window. Type chkdsk /f the /f is if an error is found to fix it if possible.

[gib]

<quote>I'm not entirely sure I understand what this "The boot still loops though," or your original post "It gets stuck in a boot - disk check loop."</quote>

Sorry, I'm not sure of the correct language to use.

The sequence is something like this, for a normal boot:

1. Disk detection screen
2. Screen with 'hit enter to start W2k or hit F8 to choose another boot mode'
3. A b&w screen with ASCII graphics progress bar
4. A colour screen with Windows banner display and a blue progress bar
5. Popup messages about loading personal settings etc
6. Popup login screen

For a normal boot with Avast installed, it goes:

1 2 3 4
7. (Sounds I associate with a reboot) Disk check screen  with 'hit any key to skip checking'
1 2 3 4 7
1 2 3 4 7
....

It doesn't make any difference whether disk checking is done or skipped.  I've let it check many times, there are no disk errors.  In every other respect the system is behaving perfectly, no hang-up on shutdown.  The disk check request is triggered somehow by Avast, presumably because of the way it jumps from 4 to a reboot.  I've never seen this happen except with Avast installed.

[DavidR]

I have never used win2k so I don't have any practical experience to call on, but the disk check is usually associated with an abnormal shut down of some sort, which means the OS notes that and will initiate the disk check on the next boot to avoid data loss, etc.

Now why this might happen with avast installed is a little beyond me, but if something was still running at shutdown avast might well still be scanning and memory may still be in use, this might cause something like this.

So what other security application do you have installed ?
Before you shutdown, check task manager (or whatever might be the win2k equivalent) and see what processes are running ?

Other than that I'm at a loss as to what else to suggest, that is me for tonight, a little after 1:10a.m. here.

[gib]

Win2k is effectively the same as XP, if that helps.
Nothing is running at shutdown, as far as I am aware.  I do not shut down while Avast is running any checks.
No other security software installed.
I have checked out the running processes by eye, with Task Manager, and also with HiJack This.  No anomalies that I can see.
The boot failure occurs in the phase when services and drivers are being started. 
I have the impression that a service that is being started causes the reboot, which then requires a disk check.  If I let the disk check execute, it still wants to do the check again when it loops around.
When I get home I'll check to see if the Avast service can be configured to start manually.  Then I'll be able to test a reboot without the service being started automatically.

By the way, I appreciate your help.

[DavidR]

Whilst win2k is an NT OS as is XP, I think there are many differences to XP in the interface, etc.

The problem is you may not know if avast is scanning (but the avast icon should be rotating) on shutdown if there is other activity. HJT wouldn't show what is actually running when you shutdown, only what starts on boot, etc.

My best guess is that the disk scan doesn't come from a service being started, but from the shutdown. The avast self-defence will make manual starting somewhat difficult, you would need to disable it, Program Settings, Troubleshooting. You might try something else from that section and that it to Delay loading of avast services after other system services and see if that makes any difference.

Other than that I'm out of ideas, we need someone from the Alwil team with a greater understanding of avast and hopefully win2k.

[gib]

Hi David,

I experimented with making the Avast services manually started.  No effect.  I activated boot logging, but didn't know enough to interpret the logs, which didn't show any obvious error messages.

With rather low expectations, I downloaded and installed the latest nVidia driver for my video card.

Problem solved.  I can now boot normally with Avast installed, services started automatically.

I'm afraid this will have to remain an ugly mystery.

Sorry to have taken so much of your time.

Regards
Gib