Unable to start download of "Specialized boot-time scan definitions"

[Robert333]

Hello,

I have Avast Free Antivirus 23.8.6078 (build 23.8.8416.794) running on Windows 8.1.

When I open: Avast > Protection > Virus Scans > Boot-Time Scan:
There is no longer any option to download "Specialized boot-time scan definitions".
Instead, this screen now only states what it would have stated had I downloaded and installed those definitions, but which of course I recently have not. Instead it now only states each time I open that screen:
"Specialized boot-time scan definitions installed."

I have tried:
Rebooting the computer.
Repairing the Avast Free Antivirus application > Repair successful.
However, the issue remains.

How can I resolve this issue please.

[mchain]

Hello.

Welcome to Avast Forums.

Thank you for your detailed information you posted.

The version Avast Free Antivirus 23.8.6078 (build 23.8.8416.794) is a bit old.  It dates from August 22, 2023 as seen here:  https://forum.avast.com/?topic=324671.0  Newest version is detailed below as an attached png file.

Unfortunately, if you downloaded the free link from the url provided, you will get the latest version 24.3.8975.0 and not 23.8.6078.  This is for safety and security reasons determined by Avast.

Any reason for running an obsolete version of Avast Free?

Recommendation:

• Repair your old version.  You can do that by going to Add/Remove programs, highlighting your installed version of Avast Free (I know it is counter-intutive) and choosing uninstall to proceed.  Along with uninstall will also be the option to repair.  Start your repair and allow the process to complete.  Restart your system when notified.
• Open Avast on reboot and check to see if you can now update your boot disk signatures

If that fails to remedy, then download the latest version to your download folder, uninstall your corrupted version and use this avast clear program to remove all traces of your old program.  https://www.avast.com/en-us/uninstall-utility#pc  Scroll down to the blue url link for 'avastclear.exe' which will then download your copy to the download folder.  Move avastclear.exe to your desktop and follow instructions to enter Safe Mode after double-clicking the executable.

Restart your system when done in Safe Mode.

Is there a reason for needing to run Boot Scan Mode in the first place?

FYI, if you haven't already done so, suggest always keeping a full sized version of the latest installation file just in case.

[Robert333]

Thank you "mchain" for your reply.

You rightfully asked:
"Any reason for running an obsolete version of Avast Free?"

Yes, the application has not had program-updates applied because I have found previously that when I apply a program-update, subsequently either the Avast interface fails to open, or it opened but then individual Avast screens fail to open.
This results in the current situation I have anyway, where I must now: uninstall, clean-uninstall, and reinstall.
Are the current program-updates more "reliable" in this respect?

You asked: "Is there a reason for needing to run Boot Scan Mode in the first place?":
Yes, it is potentially capable of detecting infected files more efficiently when Windows is not running (not running theoretically) compared to any scan running in Windows. Were that not the case Avast would not provide the Boot Time Scan.

- - - - Edit: - - - -
It is possible the view may be that Boot Scan detection is the same as the Windows Full Scan detection, and that the Boot Scan would be used if an OP had problems using the Full Scan in Windows. However, my impression is that because all other applications are off in Boot Scan, it is less likely any virus (which of course is also a program) will be running to potentially interfere not only with detection, but also with repair, or quarantine, or deletion.
- - - -

May I also enquire what you mean by: "suggest always keeping a full sized version of the latest installation file".
That implies an off-Internet Avast full-installer is available, but I believe the Avast installer is rather a management file that downloads the installation files from the Avast website - If an off-Internet Avast full-installer file is available, please confirm and let me know its Link.

Thank you.

Regards.

- - - - Edit: - - - -
I have carried out the procedure to Uninstall, Clean uninstall in Safe Mode, and Reinstall.
The new installation seems to have been successful.
I would still however, be interested in your reply to this post.

Do you happen to know why the URL for this post does not work?
When I use it, the main Avast Forums menu, that is the one that shows all the Avast Forum folders displays instead of this post.

Thank you and grateful for your assistance, but also hope to hear from you in reply.

Regards.

[rocksteady]

link for post above (to test)
https://forum.avast.com/index.php?topic=327332.msg1718138#msg1718138

EDIT: well the url for your last post works fine for me.

May I also enquire what you mean by: "suggest always keeping a full sized version of the latest installation file".

I believe that is reference to "offline installer" that is made available for download each time Avast release a new program version. I find it a good idea to save a copy of the downloaded file in case it is needed to roll back a version. See screenshot I attach for current version.

[mchain]

@Robert333,

You are welcome.

You've made my day, as I hope you did for you.  Always glad to help.   

You (and everyone else) can always go to these three urls to get the current executable files required to fix issues you may have.  Suggest bookmarking these two at the very least:

• https://forum.avast.com/index.php?topic=327113.msg1717248#msg1717248
• https://www.avast.com/installation-files#pc
• https://www.avast.com/uninstall-utility#pc

In my opinion, the best option is to always download the full offline version of the executable file you want to save.

In the second url, not all files are full size.  Most are web executables.  What that means is their online installers are a webstub exectuable, and they are all you need to download the rest of the installation file required, but you have to do it over the internet.  For example, Avast Free online installer is only 257 kb in size.  It is a starter file. 

Full-size version of Avast Free is currently 629 MB.

As rocksteady says, it is a good idea to keep a full-size copy of your installation file around, as well as the avastclear.exe file made at the same time, just in case.  One scenario is that the latest version does not work as it should and you've done the uninstall, avastclear, Safe Mode, reboot, and reinstall and it didn't work as expected.  Saving the next full-size older version will mean you have a known good installation file to go back to will have reverted successfully to a working system again.

If you are referring to our notifications to your posts, and did not get a timely notification, we are aware as some of us also have this issue.  If that is the case, know that we are working on it.

[EDIT:]  Added attachment.

[Pondus]

You asked: "Is there a reason for needing to run Boot Scan Mode in the first place?":
Yes, it is potentially capable of detecting infected files more efficiently when Windows is not running (not running theoretically) compared to any scan running in Windows. Were that not the case Avast would not provide the Boot Time Scan.

If this was the holy grail to detection then all AV vendors would use it.
 
Boot time scan is about removal/cleaning, relate to the old days when there was lots of real virus (self replicating file infectors) infecting system files and to clean these files they should not run/be in use. Malware that is detected using behaviour may not be detected with boot scan because it dont run (behave)

Boot time scan is a special tool to be used when you have problems removing something detected and not to be run as a regular scanner

[Robert333]

Having carried out the procedure to Uninstall, Clean uninstall in Safe Mode, and Reinstall Avast, although the installation appears to have been successful, after carrying out a Boot Time Scan having downloaded the Specialized boot-time definitions for it, I find that the original issue is present again!

When I open: Avast > Protection > Virus Scans > Boot-Time Scan:
There is again no longer any option to download "Specialized boot-time scan definitions".
This screen now only again, says:
"Specialized boot-time scan definitions installed."

One contributor described this issue as a "corruption" of what is now the previous installation of Avast, but having since uninstalled and reinstalled Avast and got the same issue, my impression is rather that this seems to be a software-bug, which needs be reported to Avast for a Fix.
The Specialized boot-time scan definitions are important for making the Boot Time scan successful.