Azure app breaks when updating Node version - azure

Question

I have upgraded the Node.js version to 8.8.1, and updated this in the process environmental variables, iisnode.yml, Web.config and package.json.
Nonetheless, requests going to the app now get rejected with the following error:
The iisnode module is unable to start the node.exe process. Make sure
the node.exe executable is available at the location specified in the
https://github.com/tjanczuk/iisnode/blob/master/src/samples/configuration/web.config>system.webServer/iisnode/#nodeProcessCommandLine
element of web.config. By default node.exe is expected in one of the
directories listed in the PATH environment variable.
I tried to update the file path in Kudu to reflect the path to the node.exe I'm interested in ("D:\Program Files (x86)\nodejs\8.1.1\node.exe"), but got an error saying I was not authorized to do this.
The relevant files:
iisnode.yml:
nodeProcessCommandLine: "D:\Program Files (x86)\nodejs\8.1.1\node.exe"
loggingEnabled: true
devErrorsEnabled: true
Web.config
<?xml version="1.0" encoding="utf-8"?>
<!--
For more information on how to configure your Node.js application, please visit
-->
<configuration>
<appSettings>
<!--
<add key="StorageAccountName" value="" />
<add key="StorageAccountKey" value="" />
<add key="ServiceBusNamespace" value="" />
<add key="ServiceBusIssuerName" value="" />
<add key="ServiceBusIssuerSecretKey" value="" />
-->
</appSettings>
<system.webServer>
<!-- mimeMap enables IIS to serve particular file types as specified by fileExtension. -->
<staticContent>
<mimeMap fileExtension=".svg" mimeType="image/svg+xml" />
</staticContent>
<modules runAllManagedModulesForAllRequests="false" />
<!-- Web.Debug.config adds attributes to this to enable remote debugging when publishing in Debug configuration. -->
<!--<iisnode watchedFiles="web.config;*.js;routes\*.js;views\*.pug"/>-->
<!-- Remote debugging (Azure Website with git deploy): Comment out iisnode above, and uncomment iisnode below. -->
<iisnode watchedFiles="web.config;*.js;routes\*.js;views\*.pug"
loggingEnabled="true"
devErrorsEnabled="true"
nodeProcessCommandLine="D:\Program Files (x86)\nodejs\8.8.1\node.exe --debug"/>
<!-- indicates that the server.js file is a Node.js application
to be handled by the iisnode module -->
<handlers>
<add name="iisnode" path="index.js" verb="*" modules="iisnode" />
<!-- Remote debugging (Azure Website with git deploy): Uncomment NtvsDebugProxy handler below.
Additionally copy Microsoft.NodejsTools.WebRole to 'bin' from the Remote Debug Proxy folder.-->
<add name="NtvsDebugProxy" path="ntvs-debug-proxy/blablabla" verb="*" resourceType="Unspecified"
type="Microsoft.NodejsTools.Debugger.WebSocketProxy, Microsoft.NodejsTools.WebRole"/>
</handlers>
<security>
<requestFiltering>
<hiddenSegments>
<remove segment="bin" />
</hiddenSegments>
</requestFiltering>
</security>
<rewrite>
<rules>
<clear />
<!-- Remote debugging (Azure Website with git deploy): Uncomment the NtvsDebugProxy rule below. -->
<rule name="NtvsDebugProxy" enabled="true" stopProcessing="true">
<match url="^ntvs-debug-proxy/.*"/>
</rule>
<!-- Don't interfere with requests for node-inspector debugging -->
<rule name="NodeInspector" patternSyntax="ECMAScript" stopProcessing="true">
<match url="^server.js\/debug[\/]?" />
</rule>
<rule name="app" enabled="true" patternSyntax="ECMAScript" stopProcessing="true">
<match url="iisnode.+" negate="true" />
<conditions logicalGrouping="MatchAll" trackAllCaptures="false" />
<action type="Rewrite" url="index.js" />
</rule>
</rules>
</rewrite>
</system.webServer>
<!-- Remote debugging (Azure Website with git deploy): uncomment system.web below -->
<system.web>
<httpRuntime targetFramework="4.5"/>
<customErrors mode="Off"/>
</system.web>
</configuration>

Answer 1

In iisnode.yml, you have nodeProcessCommandLine pointing to 8.1.1 instead of 8.8.1. Maybe that's just it?