SSIS to SSRS communication issue

I have an SSIS package that opens a connection to an SSRS server to generate a report in PDF format. I have done this many times in other environments and have had no problems connecting. I save the connection login info in a configuration file and the settings there are the same as the ones I use in the IDE. I have an HTTP connection manager setup to connect to the SSRS server and when I click the "Test Connection" button in the "Connection Manager Editor", the connection works fine, but when I execute the package I receive this error:

Error: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> Microsoft.SqlServer.Dts.Runtime.DtsRuntimeException: Exception from HRESULT: 0xC001600E ---> System.Runtime.InteropServices.COMException (0xC001600E): Exception from HRESULT: 0xC001600E
   at Microsoft.SqlServer.Dts.Runtime.Wrapper.IDTSHttpClientConnection100.DownloadFile(String FileName, Boolean vbOverwriteDestination)
   at Microsoft.SqlServer.Dts.Runtime.HttpClientConnection.DownloadFile(String fileName, Boolean OverwriteDestination)
   --- End of inner exception stack trace ---
   at Microsoft.SqlServer.Dts.Runtime.HttpClientConnection.DownloadFile(String fileName, Boolean OverwriteDestination)
   at ST_6b197a6290df4aff91a6881078049a14.csproj.ScriptMain.Main()
   --- End of inner exception stack trace ---
   at System.RuntimeMethodHandle._InvokeMethodFast(Object target, Object[] arguments, SignatureStruct& sig, MethodAttributes methodAttributes, RuntimeTypeHandle typeOwner)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture, Boolean skipVisibilityChecks)
   at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at System.RuntimeType.InvokeMember(String name, BindingFlags bindingFlags, Binder binder, Object target, Object[] providedArgs, ParameterModifier[] modifiers, CultureInfo culture, String[] namedParams)
   at Microsoft.SqlServer.Dts.Tasks.ScriptTask.VSTATaskScriptingEngine.ExecuteScript()

Any thoughts?