证书过期后Windows应用程序将正常工作吗

Question

We have a windows app that runs on Windows 8.1. We use a test certificate with sideloading to install the app. The key is expiring in a few days and we are in the process of generating a new one and deploying it. Meanwhile, I would like to know will the app stop working after the certificate expires? I tried to post date my device and test the app which worked even with a expired certificate. Is that the intended behaviour? I do understand for any future deployment of the app it does need a renewed certificate, but will the current version continue to work even after the certificate expired.

I tried googling and go through various articles but could not find a relevant answer.

Answer 1

The current installed version will cease to work after the cert expires. At app start up, a checking is performed on the cert that is used to sign the app, if the cert has already expired, the app can not open. The symptom is the app window is showing for a second then immediately minimized.

In your test, make sure the app is terminated (in Task Manager) before setting system time so that you won't end up testing a app resuming scenario. And you need to disconnect from corporate network since the system time can be synchronized with corporate servers. Then try to reopen the app and you should be able to observe the symptom.

Update :

I realize I was following some particular steps in my test, I first installed a package, then right before launching it for the first time, I set system time, and then launched the app. In this way, the app failed to open. The error looks like

App failed with error: Element not found.

I guess some extra deployment step which takes place in the first launch is blocked because the cert has expired. So the app cannot be activated.

If the deployed app has run at least once, looks like it can continue to work without any issue after the expiry date.

Answer 2

Recently we faced the same issue in our windows 8.1 app. The Current installed Build works normal even after the certificate expired. But the new build will not get installed as it will look for valid certificate.

Incase if you are in need to install build with expired certificate you can change the date(date before certificate expiry) and you can install the same build. After successful installation you can change the date and run the app.