Earlier this week, I started delving into Silverlight in earnest. Browsing Silverlight samples to understand what was possible with the two versions of Silverlight was great, but I very quickly became frustrated when I tried to work with the development tools.
My first problem was that I couldn't compile any of the samples: I got errors about missing references, and another that said "The Silverlight framework is not installed". I assumed that I had missed an installation step, but after lengthy checks I determined that I hadn't.
Eventually, I found a long series of postings on the Silverlight forums; after weeding through complaints from many others in the same boat and quite a bit of well-intentioned but ill-informed advice, I finally got to the crux of the problem: the Alpha tools for Visual Studio needed to be updated. The Expression Blend 2 preview also needed to be updated.
I did this, solved most of the problems, and was able to compile and debug simple samples. I still had some trouble running more complicated samples from my Visual Studio 2008 Virtual PC, even though the same samples ran fine from computers that didn't have the development tools installed.
I uninstalled the Alpha refresh runtime and tools in the Virtual PC, started over with the 1.0 RC runtime, and verified that I could browse the MLB site. Then I added the 1.1 alpha runtime, and verified that I could browse the Zero Gravity game. I retested the MLB site, and it was still OK.
Then I added the VS alpha tools, and all my samples and all the demo sites showed me "Download Silverlight" icons. When I tried to download and install Silverlight again, either 1.0 RC or 1.1 alpha refresh, I would get Error 1502, "A newer version of Silverlight is already installed on this machine."
I let the Silverlight PR team know that I was having problems, and also posted about it on the Silverlight forums. As I was about to leave the office on Friday, I got a call from Jamie Cool at Microsoft offering to help me track the problem down.
We fixed my installation in ten minutes by doing exactly the same things that I had already tried, only this time they worked. It turns out that the two builds of Silverlight, the 1.0 RC and the 1.1 Alpha, had gotten out of synch for about two days: the RC version had been bumped to fix some bugs, but the Alpha version hadn't been updated. Once I downloaded and installed the very latest 1.1 Alpha runtime and tools versions, my installation started working properly.
I like being on the leading edge. When it turns into the bleeding edge, it isn't quite as much fun.
Posted by Martin Heller on August 25, 2007 07:55 AM
