Why is Smart App Control not allowing a proper digital signed app to be installed?

Question

Smart App Control will not allow the app WBidMax to be updated or reinstalled, even though the app has a proper digital signature. It also worked last month on my Windows 11 machine. Now it will not update due to SAC. I deleted the app and tried reinstalling, but SAC blocked the install. I contacted the owner of the app and he said that it has a proper digital signature and it works on his windows 11 machine. I can right click on the .exe file and see that it has a digital signature, but the SAC still blocks it. YOU ARE MAKING ME LEAVE WINDOWS AND GOING TO APPLE, SINCE THE APP WORKS THERE. LOST CUSTOMER TO APPLE!

Answer 1

Smart App Control can be very sensitive sometimes, and may block legitimate apps, Microsoft seem to have recognised this is a problem, and in the February update they have changed Smart App Control, after that update, you will be able enable and disable Smart App Control any time you need to without needing to re-install Windows.

Answer 2

Smart App Control (SAC) may block the installation of a properly digitally signed app for several reasons, even if it worked previously. Here are some possibilities:

1. Changes in Smart App Control Policies: If the policies governing Smart App Control have been updated or changed, it could lead to previously allowed apps being blocked. This includes changes in the enforcement mode or evaluation mode settings.
2. Code Integrity Event Logs: SAC logs any executable that it blocks in the Code Integrity Event Logs. You can check these logs to see if there are specific files within the installer that are being blocked. The event IDs 3076 (evaluation mode events) and 3077 (enforcement mode events) can provide insights into what is being blocked.
3. Digital Signature Issues: Even if the app appears to have a proper digital signature, there could be issues related to the trustworthiness of the signing certificate or the way the app is packaged. If the individual files within the application package are not digitally signed, SAC may block the installation despite the overall package being signed.
4. Compatibility Issues: There may be compatibility issues with the current version of Windows 11 or the specific configuration of your machine that could lead to SAC blocking the app.

To troubleshoot, you can:

• Review the Code Integrity Event Logs for specific blocked files.
• Ensure that the app's signing certificate is trusted on your machine.
• Check if there are any updates or changes to SAC that might affect app installations.

If the issue persists, consider reaching out to Microsoft support for further assistance with Smart App Control.