angular app hosted on azure app service crashes on chrome only

Question

I have a webapi/angular website hosted on same azure appservice. so /site/api has my authentication token and other apis. and /site/app has my angular app.

Issue is, on our staging, which is not azure app service but a windows 2012 VM with IIS 7, everything works ok. I run the angular website on IE, firefox, chrome and safari, and no issues anywhere.

But then i browse my application hosted on azure website, it keeps crashing in chrome at someplaces where i have made a $http call. i get internal server 500 and i am trying but cant see more details. same angular app hosted on azure website, when browsed on IE and firefox, doesn't give me any error. I have also added verb OPTION to my web.config but not helping.

error seen in chrome : 
{Message: "An error has occurred."}
Message :"An error has occurred."

thanks.

more log data :

<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
 <System>
  <Provider Name="WWW Server" Guid="{3A2A4E84-4C21-4981-AE10-3FDA0D9B0F83}"/>
  <EventID>0</EventID>
  <Version>1</Version>
  <Level>3</Level>
  <Opcode>16</Opcode>
  <Keywords>0x100</Keywords>
  <TimeCreated SystemTime="2016-06-21T04:25:31.841Z"/>
  <Correlation ActivityID="{00000000-0000-0000-9D0F-0080000000E9}"/>
  <Execution ProcessID="76" ThreadID="5400"/>
  <Computer>RD0003FF853E2D</Computer>
 </System>
 <EventData>
  <Data Name="ContextId">{00000000-0000-0000-9D0F-0080000000E9}</Data>
  <Data Name="ModuleName">__DynamicModule_Microsoft.Owin.Host.SystemWeb.OwinHttpModule, Microsoft.Owin.Host.SystemWeb, Version=3.0.1.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35_53f2659e-bb7a-4b20-8ef3-c37bb14b89e2</Data>
  <Data Name="Notification">64</Data>
  <Data Name="HttpStatus">500</Data>
  <Data Name="HttpReason">Internal Server Error</Data>
  <Data Name="HttpSubStatus">0</Data>
  <Data Name="ErrorCode">0</Data>
  <Data Name="ConfigExceptionInfo"></Data>
 </EventData>
 <RenderingInfo Culture="en-US">
  <Opcode>MODULE_SET_RESPONSE_ERROR_STATUS</Opcode>
  <Keywords>
   <Keyword>RequestNotifications</Keyword>
  </Keywords>
  <freb:Description Data="Notification">PRE_EXECUTE_REQUEST_HANDLER</freb:Description>
  <freb:Description Data="ErrorCode">The operation completed successfully.
 (0x0)</freb:Description>
 </RenderingInfo>
 <ExtendedTracingInfo xmlns="http://schemas.microsoft.com/win/2004/08/events/trace">
  <EventGuid>{002E91E3-E7AE-44AB-8E07-99230FFA6ADE}</EventGuid>
 </ExtendedTracingInfo>
</Event>

<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
 <System>
  <Provider Name="WWW Server" Guid="{3A2A4E84-4C21-4981-AE10-3FDA0D9B0F83}"/>
  <EventID>0</EventID>
  <Version>1</Version>
  <Level>5</Level>
  <Opcode>49</Opcode>
  <Keywords>0x0</Keywords>
  <TimeCreated SystemTime="2016-06-21T04:25:31.841Z"/>
  <Correlation ActivityID="{00000000-0000-0000-9D0F-0080000000E9}"/>
  <Execution ProcessID="76" ThreadID="5400"/>
  <Computer>RD0003FF853E2D</Computer>
 </System>
 <EventData>
  <Data Name="ContextId">{00000000-0000-0000-9D0F-0080000000E9}</Data>
  <Data Name="Buffer">{&quot;Message&quot;:&quot;An error has occurred.&quot;}</Data>
 </EventData>
 <RenderingInfo Culture="en-US">
  <Opcode>GENERAL_RESPONSE_ENTITY_BUFFER</Opcode>
 </RenderingInfo>
 <ExtendedTracingInfo xmlns="http://schemas.microsoft.com/win/2004/08/events/trace">
  <EventGuid>{D42CF7EF-DE92-473E-8B6C-621EA663113A}</EventGuid>
 </ExtendedTracingInfo>
</Event>

HTTP Error 500.0 - Internal Server Error The page cannot be displayed because an internal server error has occurred.Detailed Error Information: Module __DynamicModule_Microsoft.Owin.Host.SystemWeb.OwinHttpModule, Microsoft.Owin.Host.SystemWeb, Version=3.0.1.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35_53f2659e-bb7a-4b20-8ef3-c37bb14b89e2 Notification PreExecuteRequestHandler Handler System.Web.Http.WebHost.HttpControllerHandler Error Code   0x00000000 Logon Method Bearer Logon User admin

Answer 1

the cors setting was bit off. updating web.config to below fixed it.

<add key="webpages:Version" value="2.0.0.0" />
    <add key="CORSOrigins" value="https://domainname.net" />
    <add key="CORSMethods" value="OPTIONS, GET, POST" />
    <add key="Access-Control-Allow-Headers" value="Origin, Content-Type, Depth, User-Agent, X-File-Size, X-Requested-With, If-Modified-Since, X-File-Name, Cache-Control" />