title: Error while set the System assigned manage identity for web app
body: <p>I am trying to set the system assigned managed identity On using Powershell but error displayed.</p>
  
  <pre><code>Set-AzureRmWebApp -AssignIdentity $true -Name "devt002" -ResourceGroupName "devt002RG"
  </code></pre>
  
  <p>Error :</p>
  
  <pre><code>Set-AzureRmWebApp : A parameter cannot be found that matches parameter name 'AssignIdentity'.
  At line:1 char:19
  + Set-AzureRmWebApp -AssignIdentity $true -Name "devt002" -ResourceGrou ...
  +                   ~~~~~~~~~~~~~~~
      + CategoryInfo          : InvalidArgument: (:) [Set-AzureRmWebApp], ParameterBindingException
      + FullyQualifiedErrorId : NamedParameterNotFound,Microsoft.Azure.Commands.WebApps.Cmdlets.WebApps.SetAzureWebAppCmdlet
  </code></pre>
  
  <p>Note : It is working fine when i run it in Cloud shell window.</p>