[GNC] Windows 11 security blocker

[Ken Pyzik]

Barry -- so sorry for your troubles.  Here are some possible fixes:

When GnuCash gets blocked, it’s almost always one of three things:
AVAST’s Web Shield
AVAST’s File Shield
Windows Defender’s SmartScreen.  The good news is that all three have 
clean, deterministic fixes.

1.  Confirm whether AVAST is the blocker  - AVAST usually shows a small 
toast notification like “Threat blocked” or “File moved to quarantine.”  
If you missed it:   Check AVAST’s quarantine  - Open Avast -Go to 
Protection → Quarantine.  Look for anything named gnucash‑setup.exe or 
similar.  If it’s there, restore it and mark it as Allowed.  If it’s not 
in quarantine, the block happened earlier in the chain.

2.  If AVAST Web Shield is blocking the download, this could be another 
cause.  Add a temporary exception.  Open Avast.  Go to Menu → Settings → 
Exceptions.  Add this URL:  Code  https://www.gnucash.org. Retry the 
download.   Once downloaded, you can remove the exception if you want 
to.
  AVAST sometimes flags open‑source installers because they aren’t signed 
with expensive commercial certificates, not because they’re unsafe.

3.  If AVAST File Shield blocks the installer - This happens after the 
file is downloaded.  Allow the file.  Open Avast.  Go to Protection → 
Core Shields Temporarily turn off File Shield.  Run the GnuCash 
installer.  Turn File Shield back on.  Add the installed GnuCash folder 
to Exceptions if needed.

4.  If Windows Defender SmartScreen is the blocker - SmartScreen often 
warns about “unrecognized apps.”   Bypass SmartScreen safely
When the blue warning appears:  Click More info.  Click Run anyway.  
This does not disable Defender; it just allows this one installer.

5.  If Defender is blocking the download outright - Rare, but possible.  
Check Defender’s protection history. Open Windows Security.  Go to Virus 
& threat protection.  Click Protection history. Look for a blocked item 
related to GnuCash. Choose Allow on device.

Also, make sure to verify the installer is legitimate.  Download only 
from: https://www.gnucash.org/download.phtml (gnucash.org in Bing)
Checksum verification is optional but reassuring.

Finally, do you have access to a local repair shop?  A local repair shop 
would be able to diagnose and fix your problem - I am sure of it.

Please understand -- what you are describing sounds like a problem 
inherent with your security software.  If your AVAST or Windows Defender 
have a rule to block GNUcash -- you will not get past it until you 
unblock the rule.  IMO -- Your computer has been set to NOT accept 
GNUcash.  GNUcash is open source software -- this is where the rub is.   
As an aside, try another open source program (maybe LibreOffice, 
Inkscape, or 7-zip).  If any of these downloads give you the same issue 
-- the culprit is that your computer will not accept any open source 
software.  Again - a local repair shop would be great assistance.

Best of luck-- and -- Don't be discouraged.  There is a logical reason 
for this happening -- you just have to find it.

Ken


------ Original Message ------
>From "barrym via gnucash-user" <gnucash-user at gnucash.org>
To gnucash-user at gnucash.org
Cc gnucash-user at gnucash.org
Date 1/14/2026 7:45:33 AM
Subject [GNC] Windows 11 security blocker

>Hello,
>
>You will have seen a number of messages from me about not being able to download and install GNUcash.
>
>I have examined all the options I could find for overriding  or suspending all the security systems that were on my Lenovo IdeaPad 1 running Windows 11.
>
>All the advice and suggestions that I found and tried gave me one of two results, the well known Windows etc cannot run this app, or, it is infected.
>
>I'm not sure if this is a new phenomenon applicable only to Windows 11 or Lenovo, but it exists.
>
>Apart from installing another OS has anybody any ideas? If not I am left with trying to do 2025 year end from another app or doing the job by hand.
>
>Barry
>
>
>-- This email has been checked for viruses by Avast antivirus software.
>www.avast.com
>_______________________________________________
>gnucash-user mailing list
>gnucash-user at gnucash.org
>To update your subscription preferences or to unsubscribe:
>https://lists.gnucash.org/mailman/listinfo/gnucash-user
>-----
>Please remember to CC this list on all your replies.
>You can do this by using Reply-To-List or Reply-All.