Microsoft quietly rolls out Silverlight 5.1

Summary: Microsoft made available for download Silverlight 5.1 on May 8. Here’s what’s included in this minor update.

As part of the Patch Tuesday updates delivered on May 8, Microsoft quietly delivered a minor refresh to Silverlight.

The new version (called in one place on Microsoft’s Web site 5.1, but which actually seems to be 5.2) is the first Silverlight update Microsoft has delivered since December 2011, when it rolled out Silverlight 5.

Update: Actually, the update seems to be 5.1 and not 5.2. Folks who are downloading it are reporting it is showing up as 5.1. So the 5.2 seems to be the typo on the Microsoft site. I’ve asked Microsoft to confirm the version number. Still no official word so far.

Silverlight fans shouldn’t get too excited and consider the 5.1 update as evidence that Microsoft plans to continue to put efforts into furthering its Silverlight browser plug-in and Web, desktop and mobile development platform. Microsoft occasionally advances the version number of some of its products — Internet Explorer, for example — when it delivers a patched and updated version as part of its Patch Tuesday set of security updates and fixes.

What’s new in Silverlight 5.1?  Here’s a list of some of the updates, which include performance, reliability and security improvements, according to Microsoft:

• Fixes Security issue described in the following Microsoft Knowledge Base article:
• 2636927 MS12-034
• Fixes an issue where “Best Effort” Silverlight Digital Rights Management Output Protection levels failed on some machines.
• Fixed a failure to update OOB (out of browser) applications that are configured to use elevated trust when in browser.
• Fixes an issue where persistent license acquisition would fail when a customer upgrades from Silverlight 4 to Silverlight 5.
• Fixes an issue where certain character combinations can cause Silverlight application to crash.
• Fixes an issue where Silverlight would not play content which required Output Protection.
• Fixes a Silverlight DRM issue where some customers encounter hardware ID mismatch errors which can only be resolved by re-individualization.

Microsoft officials have continued to decline to comment on the future of Silverlight beyond the Silverlight 5 release. Inside and outside the company, the word is that Silverlight 5 (and its various minor updates) will be the last major version of the platform. Microsoft said in December that the company will support Silverlight 5 until 2021.