Ever stop and think someone might have to remove or edit their avast installation in Safe Mode with a screen resolution of 640x480?
CAN’T GET TO THE REQUIRED BUTTONS TO DO THIS!
So now I have a blue screening machine that I can’t get to boot properly except to safe mode and cannot uninstall Avast to see if the most recent update is the reason for the blue screening.
Blue screening started after Avast updated and needed a restart.
Ever thought that 640x480 is a over 30 year old screen resolution?
Ever thought that you can scroll the screen?
Ever thought about telling the problem and providing details in order to get help?
Ever thought of being cordial to people who are asking for help Eddy? Many do not have your experience with computers and although their questions may be silly to you they are valid to them, they are asking for help not a smart- a** reply. They come here for help and not to be belittled by you. Now having said that I’ll admit you do help a lot of people, just sometimes not in a friendly way at times.
What is your OS?
Are you able to get into Safe Mode?
What product of Avast were you trying to uninstall? Were you using the Avast Uninstaller Tool in Safe Mode http://www.avast.com/uninstall-utility. If you can get into Safe Mode and see what is on the screen, please do so and go into Safe Mode with Networking. If you did not run the Avast Uninstaller Tool in Safe Mode, download this and save this to your desktop for future use > run it to uninstall Avast and it’s remnants. It might also be wise to go to Control Panel/Security Center > turn ON your machine’s firewall while you are in Safe Mode for protection as well. Follow the instructions of the link I posted here to uninstall Avast then reboot. But make sure you have the new version of Avast download file on your machine PRIOR to uninstalling (or do this on another machine and put it on a USB flash drive).
Turn on your regular firewall once you are in normal mode.
I suggest that you do a Custom install of the new version of Avast so that you only install the things that you want. After installing, reboot again. After this, you can update your virus definitions, configure your settings, and register it.
Let us know if you have any problems. Thank you. 
Colwarg, any other security program that is interfering? Running http://www.avast.com/uninstall-utility in Safe Mode will be the job without having to open any avast! window.
Eddy: Hardware / Software Engineer am I, please make no assumptions about my level of skill. 640x480 STILL exists as a failsafe in even windows 8, you just haven’t encountered it yet. And yes, can’t scroll the screen because the avast maintenance program is a full desktop application with no scrollbars and assuming a certain minimum screen size, thus, it’s a fail period regardless of actual screen real estate available.
The problem is that I permitted Avast to update, and on reboot, it was coughing up a blue screen with the following module at fault:
c:\program files\alwil software\avast5\ASWENGLDR.DLL
After several attempts at restarting the machine in different debugging modes, I figured that I needed to hit up safe mode, uninstall Avast, and see if I could get to desktop.
Hence the rant, the Avast update was causing the blue screen, but I couldn’t uninstall it to ensure that it was at fault and not something else.
Blue Screen Rule 1 was out the door: If an update is causing you boot problems, try uninstalling the update and see if you can boot.
I did manage to disable the avast engine while in safe mode, and rebooted again, and got another blue screen, this time from:
C:\WINNT\system32\drivers\sbhips.sys
That’s not part of Avast, that’s part of my firewall, what, why?
Regardless of whether or not Avast is tampering with my firewall, this particular module will not disable from the services module, so the only way I could get this to become “disabled” was to rename it while in safe mode. Which, after doing so, I was able to boot to the desktop.
Successful recovery from bad software update accomplished.
Step 2: Re-enable Avast and see if the blue screen caused by Avast went away.
Rude shock, can’t ENABLE Avast from services because of the protection scheme. Rather than booting into safe mode again, the Avast repair mode fixed that.
Scary time, reboot.
No blue screens.
Next step, enable firewall, nothing went boom, except while the firewall part of the firewall is working, it’s missing a component, however, it’s not a critical component because it’s part of the “Host Intrusion & Prevention System”:
“HIPS prevents attacks that reach vulnerable applications from succeeding by blocking any illegitimate behavior attempted by the affected applications.”
But that’s disabled because I’m on a router, so inbound packets only reach machines based on what port they’re on and so on, …
I’m not making assumptions at all.
Hardware/software engineer?
I’ve been working with computers since 1983.
Some people would say “I’ve seen it all”.
Not me though.
If you think you’ve seen it all something new shows up 
Like a marmot stuck in a printer.
Pigeon food in a printer.
Yes, I really have encountered that ;D
I did ask you for more information so we could try to help you.
b.t.w., good to hear you where able to solve it.
I’m still wondering what exact version of avast is installed.
Although installing avast should disable windows defender, check if it really did.
If I understand you correctly, it was (as it seems) a problem between the Sunbelt Firewall and avast.
What puzzles me is that you say you could not uninstall avast while the uninstall util is mend to run in safe-mode and you where able to boot into it.
The Avast utility program window is 710x510, putting the buttons at the bottom below the screen when the screen is at 640x480.
A marmot stuck in a printer, wow.
Just to share, I had similar issue when I went to Uninstall Avast on a older Dell Laptop xpSP3
When the utility opened in Safemode I couldn’t see the “Continue” Button at the bottom right.
luckily I could just move the screen up enough to catch the very top edge of the button.