Creating Registry Settings with WiX

Overview

You can create registry entries in the .wxs source. If you have a lot of them (like I do), then one of the better options is to create the .wxs source from the registry; Otherwise if you have a properly maintained project (like I do not) then maybe you create registry keys / values automatically in the .wxs each time a new one is introduced during the build cycle. At any rate, the basic idea is this:

You must have a component. The name is irrelevant.
You create a root RegistryKey, relative to which you can then create subkeys

Example:

    <Component Id="RegistryEntries" Guid="YET ANOTHER GUID GOES HERE" KeyPath="yes">  
        <RegistryKey Root="HKLM" Key="SOFTWARE\p-nand-q.com\blablabla\whatever\you\get\the\idea" >
                ... subkeys ...
                ... registry values ...
        </RegistryKey>
    <Component>

Oh, don't forget to add this component with a ComponentRef to your Feature!

Creating subkeys

If you have subkeys, you just create them relative to their parent key, like this:

    <Component Id="RegistryEntries" Guid="YET ANOTHER GUID GOES HERE" KeyPath="yes">  
        <RegistryKey Root="HKLM" Key="SOFTWARE\p-nand-q.com\blablabla" >
            <RegistryKey Key='whatever'>
                <RegistryKey Key='you'>
                    <RegistryKey Key='get'>
                        <RegistryKey Key='the'>
                            <RegistryKey Key='idea'>
                                ... registry values ...
                            </RegistryKey>
                            ... registry values ...
                        </RegistryKey>
                        ... registry values ...
                    </RegistryKey>
                    ... registry values ...
                </RegistryKey>
                ... registry values ...
            </RegistryKey>
        </RegistryKey>
    <Component>

Actually, I recommend adding two tags Id and ForceCreateOnInstall to the RegistryKey keys, like this:

    <Component Id="RegistryEntries" Guid="YET ANOTHER GUID GOES HERE" KeyPath="yes">  
        <RegistryKey Root="HKLM" Key="SOFTWARE\p-nand-q.com\blablabla" >
            <RegistryKey Key='whatever' Id='Key1' ForceCreateOnInstall='yes'>
                <RegistryKey Key='you' Id='Key2' ForceCreateOnInstall='yes'>
                    <RegistryKey Key='get' Id='Key3' ForceCreateOnInstall='yes'>
                        <RegistryKey Key='the' Id='Key4' ForceCreateOnInstall='yes'>
                            <RegistryKey Key='idea' Id='Key5' ForceCreateOnInstall='yes'>
                                ... registry values ...
                            </RegistryKey>
                            ... registry values ...
                        </RegistryKey>
                        ... registry values ...
                    </RegistryKey>
                    ... registry values ...
                </RegistryKey>
                ... registry values ...
            </RegistryKey>
        </RegistryKey>
    <Component>

This looks stupid and superfluous, but it is required if you later want to set registry key permissions. So how do you do that?

Setting registry key permissions

Add the option -ext WixUtilExtension.dll to both candle.exe and light.exe. So,

    
candle.exe YOUR PROJECT NAME.wxs
light.exe  YOUR PROJECT NAME.wixobj

becomes

candle.exe -ext WixUtilExtension.dll YOUR PROJECT NAME.wxs
light.exe  -ext WixUtilExtension.dll YOUR PROJECT NAME.wixobj

Change the header tag like this:

<Wix xmlns='http://schemas.microsoft.com/wix/2006/wi'
    xmlns:util='http://schemas.microsoft.com/wix/UtilExtension'

Add a <util:PermissionEx tag after the RegistryKey. For example
```
<util:Permissionx User='Everyone' GenericRead='yes' Read='yes' GenericWrite='yes' Write='yes'/>
```
grants everyone read/write access to the key. For a full list of options, refer to http://wixtoolset.org/documentation/manual/v3/xsd/util/permissionex.html
At this point you may repeat the question: why do I need Id and ForceCreateOnInstall tags for all of this? Well, because otherwise WixUtilExtension.dll will flag errors, simple as that...

At this point your build will succeed, but possibly your install fails: because the default install is not running with elevated privileges. To do so, edit the PAckage tag, like this:

    <Package Id='*' Keywords='Installer' Description="Acme's Foobar 1.0 Installer"
      Comments='Foobar is a registered trademark of Acme Ltd.' 
      Manufacturer='Wincor Nixdorf International GmbH'
      InstallPrivileges="elevated"
      InstallScope="perMachine"
      Platform="x86"
      InstallerVersion='100' Languages='1031' Compressed='yes' SummaryCodepage='1252' />

Adding values

All those keys and no values! Actually, values are fairly unexciting: they come in mostly two shapes:

<RegistryValue Name='YOUR NAME' Value='YOUR VALUE' Type='string'/> which should be obvious, and
<RegistryValue Name='YOUR NAME' Value='YOUR VALUE' Type='integer'/>.

So not a total challenge here... Refer to http://wixtoolset.org/documentation/manual/v3/xsd/wix/registryvalue.html for more options, but basically this is it...

However, to make things slightly more interesting, there is one thing you should know:

How to replace registry values with runtime variables

For example, you might want to write the installation directory into a registry value. You use ingeniously named Formatted Strings for that. In our example:

<RegistryValue Name='YOUR NAME' Value='[INSTALLDIR]' Type='string'/>

Will be replaced by the name of the directory with the Id INSTALLDIR. Obviously, this works for all other directories (and files) as well...