If you Access Application uses an application icon for the database or Forms and Reports, the Access Add-In Helper will grab and output that icon to the ACCDA build directory. However, when you install the ACCDA, MS Access does not copy the App Icon to the MS Access Add-Ins directory as it does with the .accda file, so then your Add-In is missing the correct icons.
Workaround: Manually copy your app icons to the Access Add-Ins directory. Note: This could be an issue if you have multiple Add-Ins with icons that have the same name, but are different images. For example, if you generically name all your Access app icons "app_icon.ico", there will be a naming conflict because all of the ACCDA Add-Ins get copied to a single "Access Add-Ins" directory for the user (or the local machine, depending how it is installed), when Access installs the ACCDA Add-In.
If you Access Application uses an application icon for the database or Forms and Reports, the Access Add-In Helper will grab and output that icon to the ACCDA build directory. However, when you install the ACCDA, MS Access does not copy the App Icon to the MS Access Add-Ins directory as it does with the .accda file, so then your Add-In is missing the correct icons.
Workaround: Manually copy your app icons to the Access Add-Ins directory. Note: This could be an issue if you have multiple Add-Ins with icons that have the same name, but are different images. For example, if you generically name all your Access app icons "app_icon.ico", there will be a naming conflict because all of the ACCDA Add-Ins get copied to a single "Access Add-Ins" directory for the user (or the local machine, depending how it is installed), when Access installs the ACCDA Add-In.