The Silverlight installation in all browsers is confusing, unsettling, and scary.

Update 09/2009 : you can get Microsoft's white paper and sample code about Silverlight installation.

Because of the numerous security warnings and lack of options other than to abort installation, you unfortunately get the false impression that Silverlight is a Trojan horse of sorts that "could infect and harm your computer with viruses and malicious code" with no apparent way to protect your computer other than agreeing to install it and hope for the best.

In addition you have to download a file then go find it then execute it.

It is a step that many people finds frustrating.

It will likely be a reason why they never get Silverlight installed on their machine.

And a reason I will lost them as customers.

Silverlight installation experience in FIREFOX 3:

• see: the graphic button to "Install Microsoft Silverlight" (which I put in my object tag)
• click the button
• see: "you have chosen to install Silverlight 3.0" [save file] [cancel]
• click [save file]
• click [save]
• (sit there wondering what happened)
• ...eventually ask someone what to do or get lucky and right click download message and choose "open"
• see: "silverlight 3.0.exe" is an executable file...may contain viruses...malicious code...harm your computer...use caution...are you sure?... [OK] [Cancel]
• in spite of the fear that I am infecting my computer with "viruses and malicious code", I click [OK]
• see: "Security warning...may potentionally harm your computer..." [Run] [Cancel]
• fearfully click "Run"
• says: "extracting files...Install Silverlight 3" one button: [Install Now]
• click [Install Now]
• says: "Silverlight is being installed on your computer", then shows checkbox "enable microsoft update (recommended) ... privacy statement..." [Next]
• click [Next]
• says: "Installation Successful, you may have to refresh the web page..." [Close]
• click [Close]
• go back to web page and click the refresh button on browser
• I see the silverlight application, success.

Silverlight installation experience in INTERNET EXPLORER 6/7/8:

• see: the graphic button to "Install Microsoft Silverlight" (which I put in my object tag)
• click the button
• see: "To help protect your security...blocked this site from downloading files to your computer" and "did you notice the information bar" [OK]
• click [OK]
• (sit there wondering what to do)
• finally click the bar on top, see "what's the risk?" click "download file" anyway
• see: "Security warning...may potentionally harm your computer..." [Run] [Cancel]
• click [Run]
• watch it download, 15 seconds
• see: "Security warning...can potentially harm your computer" [Run] [Don't Run]
• click [Run]
• says "Install Silverlight 3" one button: [Install Now]
• click [Install Now]
• says: "Silverlight is being installed on your computer", then shows checkbox "enable microsoft update (recommended) ... privacy statement..." [Next]
• click [Next]
• says: "Installation Successful, you may have to refresh the web page..." [Close]
• click [Close]

Someone answered:

Well, considering you now know what steps the user is going to have to do you could create a help page for the user. Granted, it isn't the best thing (a simplified install experience would be better, obviously) but at least the user would be able to easily find steps on what is going on.

Source: http://stackoverflow.com/questions/523596/how-to-improve-the-much-to-be-desired-silverlight-installation-experience