Installing .appx without trusted certificate?

Question

I have a Windows 8 app that I would like to deploy to my Windows RT 2. I only have the .appx, and I would like to just install it for testing by bypassing the s

Answer 1

If you're getting this error: App installation failed with error message: Install failed. Please contact your software vendor. (0x80073cf9) Please check you might already installed this app. Please uninstall and try again

Answer 2

Doesn't work for me. I still get the error after installing the certificate

If you received the message,

Either you need a new certificate installed for this app package, or you need a new app package with trusted certificates. Your system administrator or the app developer can help. A certificate chain processed, but terminated in a root certificate which isn't trusted (0x800B0109)

after renew your certificate, than probably your certificate is a temporary one and the simple way to solve it is make it usable.

To correct this error you need to change the position of certificate to root trusted certificates folder. When you click in your certificate, appear a page that ask you where you want to install it. So, there, you need to change to root trusted certificate folder and not use the default.

Regards

Answer 3

1. Double-click the Package_1.0.6.0_AnyCPU_Debug.cer file
2. Click the Install Certificate... button
3. Store Location -> Local Machine
4. Select the Place all certificates in the following store
5. Click Browse... button
6. Select the Trusted Root Certification Authorities
7. OK

Answer 4

The certificate is probably self-signed, so you need to install it to trust it.

Obtain the Certificate that signed the App

If this is your own app, you should be able to find it in your IDE ( e.g. Visual Studio) otherwise use these steps:

1. Right click on APPX file
2. Click Properties
3. Click Digital Signatures
4. Select Signature from the list
5. Click Details
6. Click View Certificate
7. Click Install Certificate

Install the Certificate

Quote from Installing developer packages on Windows RT:

1. From the Windows RT PC, either map the network share or connect the USB drive where you can access the AppPackages folder that contains the app package to install. Use Windows Explorer to open that folder.
2. Double-tap the certificate file in the folder and then tap Install Certificate. This displays the Certificate Import Wizard.
3. In the Store Location group, tap the radio button to change the selected option to Local Machine.
4. Click Next. Tap OK to confirm the UAC dialog.
5. In the next screen of the Certificate Import Wizard, change the selected option to Place all certificates in the following store.
6. Tap the Browse button. In the Select Certificate Store pop-up window, scroll down and select Trusted People, and then tap OK.
7. Tap the Next button; a new screen appears. Tap the Finish button.
8. A confirmation dialog should appear; if so, click OK. (If a different dialog indicates that there is some problem with the certificate, you may need to do some certificate troubleshooting. However, describing what to do in that case is beyond the scope of this topic.)

See also:

• Installing developer packages on Windows RT

Answer 5

For me this was occurring when trying to install Side-load HockeyApp version

Fix:

Before installing: Enable Developer mode at

Settings ➔ Update & Security ➔ For Developers ➔ Use Developer features : Developer Mode

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Install certificate (.cer file) to Trusted root certificates.

• Store location = Local machine
• Place all certificates in the following store = Third-Party Root Certification Authorities

Then retry