Stand alone deployments...

Question

We've been using Lightswitch to target laptops and tablets. The apps are many and varied, and Lightswitch provides a great framework to package and deploy complex sophisticated apps. We then use some home grown routing and network connectivity code to synchronize with app services in the cloud.

We have found that upgrading the installed apps is a challenge, we get a COM error when trying to perform a device update. To work around this we have had to either rename the application, or remove and re-install.

We have a work around, just wondered if there are any other reports like this. We have a large >1000 number of devices in the pipeline for rollout, so a fix would be great, but we can work around it if low on the fix/release schedule.

Thanks,

Steve 

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Steve

Answer 1

To update desktop apps, you need to have signed the XAP file when you originally published the app, and you need to re-sign it with the same key when you publish updates.

XAP signing is a requirement for silverlight app updates.

Answer 2

Hi Matt,

I appreciate that is true when publishing to Azure, but is that true for a stand alone deployment? I'm sure we didn't have a certiifcate to sign the XAP file for the initial installation. I'll check and get back to you in terms of how we did it. However that might explain the upgrade issue?

Thanks,

Steve

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Steve

Answer 3

RIght.  You can publish and install the app initially even though it is unsigned.  However, to upgrade the app, it had to have been signed and the update has to be signed with the same key.

Answer 4

Hi Matt,

We tried it unsigned, and signed with our own self certified certificate.

We even tried uninstalling and re-installing from scratch. Once an App had been installd we had to rename the app before we could get it installed again.

Thanks,

Steve

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Steve

Answer 5

To use self-signed certs you need to import the cert into the client into the right store such that sllauncher (the silverlight OOB host) beleives that it is trusted.  You need to have this setup before you do the first install of the app, in my experience.

I apologize for all of the trouble this is.  The SL runtime needs to work this way for security reasons, but we're not aware of a way to turn off the "thoroughly scrutinize certificates" behavior that SL provides.

Answer 6

Thanks Matt, appreciate the insight.

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Steve