Sometimes, when you have a complex setup which contains both web related components and other components.
For example:
<Component Id=“WebComponent“ Guid=“4f85112d-2084-49e1-abb5-0631e842dfb4“>
<CreateFolder/>
<iis:WebSite Id=“DefaultWebSite“ Description=“Default Web Site“ Directory=“INSTALLLOCATION“>
<iis:WebAddress Id=“AllUnassigned“ Port=“80“ />
</iis:WebSite>
<iis:WebVirtualDir Id=“VirtualDir“ Alias=“vdir“ Directory=“INSTALLLOCATION“ WebSite=“DefaultWebSite“>
<iis:WebApplication Id=“WebApplication“ Name=“vdir“ />
</iis:WebVirtualDir>
</Component>
<Component Id=“NoWebComponent“ Guid=“4b852c0b-43e0-47b1-99ec-a1e80dc06f6e“>
<File Id=“F_README“ Source=“readme.txt“ Name=“readme.txt“/>
</Component>
But despite the fact that no web related features were selected, installer fails with message that it cannot connect to iis. It turns out that ConfigureIIs custom action is executed. In WiX version 3 you can disable this action with:
<InstallExecuteSequence>
<Custom Action=“ConfigureIIs“ After=“InstallFiles“>$WebComponent>2</Custom>
</InstallExecuteSequence>