The script adds TEL: and SIP: attributes to Lync so you can select it as a default application in the list of capable clients.
I have created a simple script that I use on my Windows 8 machines to reset the URL assosciations for TEL:, SIP:, mailto: and Lync meetings. Script to reset all Lync related URL associations Find a SIP: link and click Lync (Desktop) when asked for the default application.Set-ItemProperty HKLM:\Software\Microsoft\Office\15.0\Lync\Capabilities\URLAssociations -name SIP -value Microsoft.Lync.15Join.1.Remove-ItemProperty HKCU:\Software\Microsoft\Windows\Roaming\OpenWith\UrlAssociations\sip\UserChoice -Name Hash.Remove-ItemProperty HKCU:\Software\Microsoft\Windows\Shell\Associations\UrlAssociations\sip\UserChoice -Name Hash.To make sure Lync is your preferred SIP: client run the following registry settings from PowerShell run as administrator.Usually SIP is will open by default in Lync and you can not change the default program for SIP in GUI.Read more in this article by MVP Jeff Guillet:.Then you can go in to Default Programs->Associate a file type or protocol and change the default program for TEL:.Add this registry setting from PowerShell run as administrator: Set-ItemProperty HKLM:\Software\Microsoft\Office\15.0\Lync\Capabilities\URLAssociations -name TEL -value Microsoft.Lync.15Join.1.For TEL: you first need to add the Lync 2013 Rich Client to the list of clients that can do TEL: links.Read more in this article by MVP Johan Delimond:.For Lync meetings and mailto you can change this in GUI by going in to Default Programs->Associate a file type or protocol with a program and change the default program.
How to change your default applications for these URL’s
Lync Rich (desktop) client – Opens TEL:, SIP: and Lync meeting links.This article will help you take control of your Unified Communications links. This can be a problem since it may not always be the application you want to use that is opening your links. On a windows 8 machine you can have several application that can open Lync and Outlook related URL’s.