I have a computer with Windows 7 Home x64 SP1 installed (still receiving regular updates from MS) with Avast Premium installed. Until September 11 everything worked fine. On Wednesday morning Windows suddenly crashed, and all attempts to reboot it shown the message “A disk read error occurred. Press Ctrl+Alt+Del to restart” on the black screen, even without arriving to “Starting Windows” and colored logo screen.
I checked the disk with bootable USB utilities including chkdisk, HDDScan, etc - everything is normal and no broken clusters or something like this was not found, so the SSD is fine.
Hopefully :), I have a previous SSD of smaller capacity (not used for more than a year) with the same Win7 installed, and also installed Avast Premium. I replaced the SSD and was able to run Win7 and all programs :). However, on the next day this second SSD had a Windows 7 crash :-[ with blue screen indicating it makes memory dump. After the reboot I received on this second SSD the same message “A disk read error occurred. Press Ctrl+Alt+Del to restart”! After several restarts the messages changed to “Windows failed to restart. A recent software or hardware change might be the cause.” and the same black screen proposed to use Windows installation disk to repair the system, and also shown the message “Info: Windows failed to load because the kernel is missing, or corrupt. File \Windows\system32\ntoskrnl.exe”. After the next reboot the message “Windows failed to restart. A recent software …” was accompanied with the details “Info: An error occurred while attempting to read the boot configuration data. File \EFI\Microsoft\Boot\BCD”. >:(
After next reboots I was able to enter Windows Safe Mode. I run “sfc \scannow” to check Windows integrity, everything was normal, no any errors in ntoskrnl.exe or any other files. Considering that only “recent software change” on this old SSD that I didn’t use for months could be only antivirus, I uninstalled all Avast products (antivirus, and cleaner or something like that).
On the next reboot after removing Avast the Windows 7 started normally! So, the only reason for not able to boot the Windows and all messages about the “kernel is missing, or corrupt” were related to conflict caused by Avast!
While trying to figure out what can cause windows boot failure with normal SSD, I searched in internet and found that previously Avast caused a kind of similar problem with Win7 but x32 (while I run Win 7 x64) - couldn’t provide the link because searched from my phone while Windows was unable to boot.
Now, there are 3 main questions:
- How can I remove Avast from the Windows that is not able to boot due to conflict with Avast?
The initial SSD with Windows 7 x64 SP1 installed and Avast is not functioning and shows only “A disk read error occurred. Press Ctrl+Alt+Del to restart” message, with no possibility to enter Safe Mode and remove Avast.
The only solution would be to use bootable USB with some Avast remover, but as far as I can understand there is no such solution. The official avastcleaner that is able to remove Avast can only run from Windows (in my case I can not boot Windows thanks to Avast conflict).
2. Is it possible to roll back recent changes either in Avast antivirus signatures database or in Avast executables? Considering that before the morning September 11 everything worked fine, the day before the Avast introduced some antivirus signatures or its executables that causes the conflict with Win 7 and does not allow to boot it. I think that if I rollback to previous (September 10) Avast state, everything will work. And then I can prohibit auto-updates, until the Avast will correct the problem.
- When Avast will reveal what caused the conflict and correct the antivirus signatures database and/or its executables that caused the conflict, how I will know about it? I will prohibit Avast auto-updates, but I do not want to wait until the New Year to receive the updates that will not conflict with Win7 boot. I paied for the Avast Premium, and want to use it instead of throwing several days on revealing why Avast caused conflict with Windows.