title: Azure Functions, "System.Private.CoreLib: Value cannot be null. (Parameter 'path1'). Value cannot be null. (Parameter 'provider')"
body: <p>I'm running Azure functions/core tools 3.x, in my Gradle (version 4.6) Java (JDK 1.8) project with azure functions apps. I have a GET endpoint at localhost:7071 at api/devices I am trying to hit, but I keep getting errors running <strong>azureFunctionsRun.</strong></p>
  
  <p>When I run azureFunctionsPackage, it seems to work fine. When I run azureFunctionsRun, I get the error posted below. When I used to be on azure core tools 2.x, I was apple to use the command "func start", and everything worked flawlessly. I have the host.json file with the boilerplate version and ExtensionBundles script and local.settings.json with a connection string for my Azure Web Jobs Storage:</p>
  
  <pre><code>Azure Functions Core Tools found.
  Starting running Azure Functions...
  Executing command: cmd.exe /c cd /D C:\git\edge_bootstrap_ms\build\azurefunctions\edge-bootstrap-ms &amp;&amp; func host start
  
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  Azure Functions Core Tools (3.0.2106 Commit hash: 5431fca4f603bf9446d7dd2d5f96a43b5f69b5cb)
  Function Runtime Version: 3.0.13107
  [3/18/2020 8:56:57 PM] FUNCTIONS_WORKER_RUNTIME set to java. Skipping WorkerConfig for language:node
  [3/18/2020 8:56:57 PM] FUNCTIONS_WORKER_RUNTIME set to java. Skipping WorkerConfig for language:powershell
  [3/18/2020 8:56:57 PM] FUNCTIONS_WORKER_RUNTIME set to java. Skipping WorkerConfig for language:python
  [3/18/2020 8:56:57 PM] Starting worker process:C:\Program Files\Java\jdk1.8.0_241\bin\java  -XX:+TieredCompilation -XX:TieredStopAtLevel=1 -noverify -Djava.net.preferIPv4Stack=true -jar "C:\Users\KBRV37\AppData\Roaming\npm\node_modules\azure-functions-core-tools\bin\workers\java\azure-functions-java-worker.jar" --host 127.0.0.1 --port 61509 --workerId 9ff09cf4-42d8-4e1a-b66e-8058754fe61a --requestId 123c617a-61e1-4b3a-98d8-13b6a5eff6c1 --grpcMaxMessageLength 134217728
  [3/18/2020 8:56:57 PM] C:\Program Files\Java\jdk1.8.0_241\bin\java process with Id=10984 started
  [3/18/2020 8:56:57 PM] [INFO] {Application.main}: Azure Functions Java Worker  version [ 1.5.2-SNAPSHOT]
  [3/18/2020 8:56:58 PM] [INFO] {MessageHandler.handle}: Message generated by "StartStream.Builder"
  [3/18/2020 8:56:59 PM] Building host: startup suppressed: 'False', configuration suppressed: 'False', startup operation id: '078289ce-7cd5-4f2f-924b-40696702867a'
  [3/18/2020 8:56:59 PM] Reading host configuration file 'C:\git\edge_bootstrap_ms\build\azurefunctions\edge-bootstrap-ms\host.json'
  [3/18/2020 8:56:59 PM] Host configuration file read:
  [3/18/2020 8:56:59 PM] {
  [3/18/2020 8:56:59 PM]   "version": "2.0",
  [3/18/2020 8:56:59 PM]   "extensionBundle": {
  [3/18/2020 8:56:59 PM]     "id": "Microsoft.Azure.Functions.ExtensionBundle",
  [3/18/2020 8:56:59 PM]     "version": "[1.*, 2.0.0)"
  [3/18/2020 8:56:59 PM]   }
  [3/18/2020 8:56:59 PM] }
  [3/18/2020 8:56:59 PM] Reading functions metadata
  [3/18/2020 8:56:59 PM] 3 functions found
  [3/18/2020 8:56:59 PM] Looking for extension bundle Microsoft.Azure.Functions.ExtensionBundle at (null)
  [3/18/2020 8:56:59 PM] Fetching information on versions of extension bundle Microsoft.Azure.Functions.ExtensionBundle available on https://functionscdn.azureedge.net/public/ExtensionBundles/Microsoft.Azure.Functions.ExtensionBundle/index.json
  [3/18/2020 8:56:59 PM] A host error has occurred during startup operation '078289ce-7cd5-4f2f-924b-40696702867a'.
  [3/18/2020 8:56:59 PM] System.Private.CoreLib: Value cannot be null. (Parameter 'path1').
  Value cannot be null. (Parameter 'provider')
  Application is shutting down...
  [3/18/2020 8:56:59 PM] Initialization cancellation requested by runtime.
  [3/18/2020 8:56:59 PM] Shutting down language worker channels for runtime:java
  [3/18/2020 8:56:59 PM] Stopping host...
  [3/18/2020 8:56:59 PM] Host shutdown completed.
  :azureFunctionsRun FAILED
  1 actionable task: 1 executed
  
  FAILURE: Build failed with an exception.
  </code></pre>
  
  <p>Host.json:</p>
  
  <pre><code>{
    "version": "2.0",
    "extensionBundle": {
      "id": "Microsoft.Azure.Functions.ExtensionBundle",
      "version": "[1.*, 3.0.0)"
    }
  }
  </code></pre>
  
  <p>local.settings.json:</p>
  
  <pre><code>{
    "IsEncrypted": false,
    "Values": {
      "AzureWebJobsStorage": "DefaultEndpointsProtocol=https;AccountName=myAzureAccountName;AccountKey=myAzureAccountKeyString==",
      "FUNCTIONS_WORKER_RUNTIME": "java"
    }
  }
  </code></pre>