SL 4 Version Hell ?? The silverlight developer runtime is not installed please install a matching version

Question

I've been developing for and running Silverlight 4 for about a week. A week ago I installed the Silverlight 4 design time components to develop and debug silverlight for VS 2010 - I posted some of these apps and they were used by users running SL4. Today, I went to a website that told me to upgrade my SL (I think it was the MS expression site) - so I did that and all the sudden I get this error when running SL 4 apps within VS 2010.

The silverlight developer runtime is not installed please install a matching version

Installing the latest version of the Silverlight SDK does not correct this. Basically I am stuck and unable to run Silverlight apps from VS2010.

Are versioning problems like this a common theme in SilverLight? The only thing I can think of is that there is a minor version difference between the versions used on the the MS Expression web site and the version (SL4) I installed from MS site a few days ago? However re-installing the latest version of SL4 does not correct this.

Any help?

Answer 1

I stole this answer from Tim Heuer

http://timheuer.com/blog/archive/2010/06/30/silverlight-top-issues-reported.aspx

Installation and deployment I’ve seen this a lot. People saying that they have Silverlight installed and they went to a website that prompted them to install Silverlight, so they did (again) and they went back and were prompted again…rinse, repeat. The other is that people (your users) aren’t getting prompted for upgrades properly or they aren’t working well with applications.

It is true that we put a lot of responsibility on the developer to customize the installation experience for the developer. I’ve written about this a few times. In fact, I called out what I believe to be the best encapsulation of the tenets of a good experience in what Netflix does: Silverlight Install Best Practices. We have also posted a whitepaper on the Silverlight community whitepaper area for the Silverlight Installation Experience Guidance which basically incorporates these tenets into guidance and sample code as well. This is a helpful whitepaper to understand the events of the plugin in upgrade situations and how easily you can handle them.

Most of the support issues we see are because the application isn’t properly handling these situations. One could ask that why we, Microsoft, aren’t providing a better default template that includes all these best practices. We’ve wrestled with this idea quite a bit actually. In the end, we didn’t feel right now we could come up with a universal application template that would meet the needs of all app developers (different sizes, use cases for their Silverlight app). Some things are easier such as media applications coming from Expression Encoder, for example, where we know the size and use of the application. In fact, those templates have already been enhanced for a better experience than the default install badge. It is still on our list to provide better out-of-the-box templates in Visual Studio, but we balance that with other features that are on the list for prioritization for customers.

In the end, this is a very solvable issue and again it appears that discovery of the solution could be better. Help me understand how we can better surface this?