Indexing error with MongoDB that should be disabled

Question

I'm getting the below error in my Crawling.log.txt file. The problem is that we don't have MongoDB or xDB setup because we're not using it at all. I'm trying to figure out where this is coming from.

ManagedPoolThread #2 09:28:54 ERROR Could not compute value for ComputedIndexField: potential for indexable: sitecore://master/{2DEEEFEE-B008-4CB0-BB9E-EE1DD8034F3B}?lang=en&ver=1
Exception: System.Reflection.TargetInvocationException
Message: Exception has been thrown by the target of an invocation.
Source: mscorlib
   at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
   at System.Reflection.RuntimeConstructorInfo.Invoke(BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
   at Sitecore.Reflection.ReflectionUtil.CreateObject(Type type, Object[] parameters)
   at Sitecore.Configuration.DefaultFactory.CreateFromTypeName(XmlNode configNode, String[] parameters, Boolean assert)
   at Sitecore.Configuration.DefaultFactory.CreateObject(XmlNode configNode, String[] parameters, Boolean assert, IFactoryHelper helper)
   at Sitecore.Configuration.DefaultFactory.CreateObject(XmlNode configNode, String[] parameters, Boolean assert)
   at Sitecore.Configuration.DefaultFactory.GetInnerObject(XmlNode paramNode, String[] parameters, Boolean assert)
   at Sitecore.Configuration.DefaultFactory.AssignProperties(XmlNode configNode, String[] parameters, Object obj, Boolean assert, Boolean deferred, IFactoryHelper helper)
   at Sitecore.Configuration.DefaultFactory.CreateObject(XmlNode configNode, String[] parameters, Boolean assert, IFactoryHelper helper)
   at Sitecore.Configuration.DefaultFactory.CreateObject(XmlNode configNode, String[] parameters, Boolean assert)
   at Sitecore.Configuration.DefaultFactory.CreateObject(String configPath, String[] parameters, Boolean assert)
   at Sitecore.Analytics.Reporting.ReportingQueryBase..ctor(ReportDataProviderBase reportProvider, CachingPolicy cachingPolicy)
   at Sitecore.ContentTesting.Analytics.Reporting.TimeRangeItemBasedReportingQuery..ctor(ID queryItemId, ReportDataProviderBase reportProvider, CachingPolicy cachingPolicy)
   at Sitecore.ContentTesting.Analytics.Reporting.TestPotentialQuery..ctor(ReportDataProviderBase reportProvider)
   at Sitecore.ContentTesting.ContentSearch.ComputedIndexFields.TestPotentialMetricBase.ComputeFieldValue(IIndexable indexable)
   at Sitecore.ContentSearch.Azure.CloudSearchDocumentBuilder.AddComputedIndexFields()

Nested Exception

Exception: System.NullReferenceException
Message: Object reference not set to an instance of an object.
Source: Sitecore.Analytics.MongoDB
   at Sitecore.Analytics.Reporting.MongoDbReportDataSource..ctor(String connectionStringName)

Answer 1

From your question, it is clear that you are not using analytics so this is CMS only mode. From my past experience, Content testing will not work properly with CMS mode only. The same thing you can see in the log, where Sitecore Content testing is trying to access the analytics.

So to resolve the above problem you need to disable the content testing. For disabling the content testing for Sitecore 8.1 or later, change the ContentTesting.AutomaticContentTesting.Enabled setting value to false in the App_Config\Include\ContentTesting\Sitecore.ContentTesting.config file:

<setting name="ContentTesting.AutomaticContentTesting.Enabled" value="false" />

or see KB article for disabling the content testing - https://kb.sitecore.net/articles/785358