Sigil 2.8.1 blocked by Windows 11 Smart App Control

Hillbilly · Yesterday, 06:33 PM

I'm running Sigil 2.8.1.0 on Windows 11 25H2. I've used Sigil for quite a while and have a highly customized installation with a number of plugins.

Windows Smart App Control has now started completely blocking Sigil from running, with the message that the app may be unsafe because the publisher can't be verified. There is no "Run anyway" option with Smart App Control.

I checked Sigil.exe Properties and it has no Digital Signatures tab/signature.

I also checked Event Viewer under Microsoft > Windows > CodeIntegrity > Operational immediately after attempting to launch Sigil. The event says:

"Code Integrity determined that a process (...) attempted to load ...\Program Files\Sigil\Sigil.exe that did not meet the Enterprise signing level requirements or violated code integrity policy."

Smart App Control is currently On. Windows provides no per-app exception, and on my machine Windows Security warns that if I turn Smart App Control off, I won't be able to turn it back on without reinstalling Windows.

I know Sigil recommends installing via winget to avoid Microsoft's unknown-publisher warnings, but I'm reluctant to reinstall a heavily customized working installation - especially since I'm already running the current 2.8.1 release.

Is there a signed Windows build of Sigil available, or are there plans to Authenticode-sign future Windows releases? And does installing 2.8.1 via winget actually solve Smart App Control blocking Sigil.exe itself, rather than just avoiding the usual SmartScreen/unknown-publisher warning? Thanks in advance!

KevinH · Yesterday, 06:39 PM

Install using winget. Sigil Preferences folder which holds all plugins, settings, and checkpoints is not impacted by an install.

Hillbilly · Yesterday, 06:41 PM

Will do, thank you!

KevinH · Yesterday, 06:43 PM

No signed version is planned. Smart App Control is basically being very "dumb" here. If I told my os to run what I knew to be safe and it refused with no way to tell it I trust that app, I would move to an OS that literally did what I told it to.

KevinH · Yesterday, 06:51 PM

In fact from a web search, Smart App Control for Business will allow the creation of manual exceptions. Sounds like a reason to upgrade.

DiapDealer · Yesterday, 07:10 PM

It is my understanding that Windows 11 25H2 should allow users to re-enable SAC without needing to reset or reinstall Windows. There were certainly updates that claimed this to be the case.

I'm afraid I am utterly unwilling to pay the exorbitant ransoms required to become a "Known" publisher of software that runs on Windows. This is purely a hobby for me.

DiapDealer · Yesterday, 07:36 PM

I just noticed that with the update to Windows 11 26H2, I can now granularly disable the reputation based protection nonsense that would trigger smart screen warnings on downloads in the past. This is good news for me!

DNSB · Yesterday, 07:41 PM

My personal choice the first time Windows Smart App control blocked an app I had been using for years was to click the Off button. So far, I have not regretted that decision. Windows 11 26H2 here and I still have the need to reinstall Windows to reenable Windows Smart App control shown below the off button.

DiapDealer · Yesterday, 07:44 PM

For what it's worth: I'm also able turn off SAC and re-enable it with no warning message about needing to reset/reinstall Windows on 26H2. But even with SAC enabled, it wasn't trying to block a very recent build of Sigil from running.

DiapDealer · Yesterday, 08:05 PM

I cannot swear that installing Sigil via winget will get around the SAC blockade (especially if it's looking specifically for a digital signature), but the vetting/scanning done by the winget intake process always eliminated the smart screen warnings about unknown publishers (and low reputation). But even those warnings could always be bypassed even if Sigil was not installed via winget. SAC seems like a bit of a game changer. But it's something I'd have no problem turning off. Even if doing so cost me the ability to ever turn it back on again. It's ridiculously invasive and over-protective. Cloud based security analysis that unilateral decides if something is safe to run on my machine (with no option to bypass it for that app)? No thank you.

Yesterday, 06:33 PM	#1
Hillbilly Junior Member Posts: 2 Karma: 10 Join Date: Oct 2026 Device: Sigil	Sigil 2.8.1 blocked by Windows 11 Smart App Control I'm running Sigil 2.8.1.0 on Windows 11 25H2. I've used Sigil for quite a while and have a highly customized installation with a number of plugins. Windows Smart App Control has now started completely blocking Sigil from running, with the message that the app may be unsafe because the publisher can't be verified. There is no "Run anyway" option with Smart App Control. I checked Sigil.exe Properties and it has no Digital Signatures tab/signature. I also checked Event Viewer under Microsoft > Windows > CodeIntegrity > Operational immediately after attempting to launch Sigil. The event says: "Code Integrity determined that a process (...) attempted to load ...\Program Files\Sigil\Sigil.exe that did not meet the Enterprise signing level requirements or violated code integrity policy." Smart App Control is currently On. Windows provides no per-app exception, and on my machine Windows Security warns that if I turn Smart App Control off, I won't be able to turn it back on without reinstalling Windows. I know Sigil recommends installing via winget to avoid Microsoft's unknown-publisher warnings, but I'm reluctant to reinstall a heavily customized working installation - especially since I'm already running the current 2.8.1 release. Is there a signed Windows build of Sigil available, or are there plans to Authenticode-sign future Windows releases? And does installing 2.8.1 via winget actually solve Smart App Control blocking Sigil.exe itself, rather than just avoiding the usual SmartScreen/unknown-publisher warning? Thanks in advance!

Yesterday, 06:39 PM	#2
KevinH Sigil Developer Posts: 10,146 Karma: 7640000 Join Date: Nov 2009 Device: many	Install using winget. Sigil Preferences folder which holds all plugins, settings, and checkpoints is not impacted by an install. Last edited by KevinH; Yesterday at 06:44 PM.

Yesterday, 08:05 PM	#10
DiapDealer Grand Sorcerer Posts: 29,860 Karma: 212614993 Join Date: Jan 2010 Device: Nexus 7, Kindle Fire HD	I cannot swear that installing Sigil via winget will get around the SAC blockade (especially if it's looking specifically for a digital signature), but the vetting/scanning done by the winget intake process always eliminated the smart screen warnings about unknown publishers (and low reputation). But even those warnings could always be bypassed even if Sigil was not installed via winget. SAC seems like a bit of a game changer. But it's something I'd have no problem turning off. Even if doing so cost me the ability to ever turn it back on again. It's ridiculously invasive and over-protective. Cloud based security analysis that unilateral decides if something is safe to run on my machine (with no option to bypass it for that app)? No thank you. Last edited by DiapDealer; Yesterday at 08:35 PM.

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Yesterday, 06:41 PM	#3
Hillbilly Junior Member Posts: 2 Karma: 10 Join Date: Oct 2026 Device: Sigil	Will do, thank you!

Yesterday, 06:43 PM	#4
KevinH Sigil Developer Posts: 10,146 Karma: 7640000 Join Date: Nov 2009 Device: many	No signed version is planned. Smart App Control is basically being very "dumb" here. If I told my os to run what I knew to be safe and it refused with no way to tell it I trust that app, I would move to an OS that literally did what I told it to.

Yesterday, 06:51 PM	#5
KevinH Sigil Developer Posts: 10,146 Karma: 7640000 Join Date: Nov 2009 Device: many	In fact from a web search, Smart App Control for Business will allow the creation of manual exceptions. Sounds like a reason to upgrade.

Yesterday, 07:10 PM	#6
DiapDealer Grand Sorcerer Posts: 29,860 Karma: 212614993 Join Date: Jan 2010 Device: Nexus 7, Kindle Fire HD	It is my understanding that Windows 11 25H2 should allow users to re-enable SAC without needing to reset or reinstall Windows. There were certainly updates that claimed this to be the case. I'm afraid I am utterly unwilling to pay the exorbitant ransoms required to become a "Known" publisher of software that runs on Windows. This is purely a hobby for me.

Yesterday, 07:36 PM	#7
DiapDealer Grand Sorcerer Posts: 29,860 Karma: 212614993 Join Date: Jan 2010 Device: Nexus 7, Kindle Fire HD	I just noticed that with the update to Windows 11 26H2, I can now granularly disable the reputation based protection nonsense that would trigger smart screen warnings on downloads in the past. This is good news for me!

Yesterday, 07:41 PM	#8
DNSB Bibliophagist Posts: 55,292 Karma: 182532776 Join Date: Jul 2010 Location: Vancouver Device: Kobo Sage, Libra Colour, Lenovo M8 FHD, Paperwhite 4, Tolino epos	My personal choice the first time Windows Smart App control blocked an app I had been using for years was to click the Off button. So far, I have not regretted that decision. Windows 11 26H2 here and I still have the need to reinstall Windows to reenable Windows Smart App control shown below the off button.

Yesterday, 07:44 PM	#9
DiapDealer Grand Sorcerer Posts: 29,860 Karma: 212614993 Join Date: Jan 2010 Device: Nexus 7, Kindle Fire HD	For what it's worth: I'm also able turn off SAC and re-enable it with no warning message about needing to reset/reinstall Windows on 26H2. But even with SAC enabled, it wasn't trying to block a very recent build of Sigil from running.