Q:

How to resolve errors with Event IDs 6482 and 6398 in SharePoint 2013?

In my event log I see this error generating every minute (Event ID 6482):

Application Server Administration job failed for service instance Microsoft.Office.Server.Search.Administration.SearchServiceInstance
  (e1df40b4-a364-47af-a4fa-69e010bf3893). Reason: A call to SSPI failed,
  see inner exception. Technical Support Details:
  System.ServiceModel.Security.SecurityNegotiationException: A call to
  SSPI failed, see inner exception. --->
  System.Security.Authentication.AuthenticationException: A call to SSPI
  failed, see inner exception. --->
  System.ComponentModel.Win32Exception: The target principal name is
  incorrect    --- End of inner exception stack trace ---    at
  System.Net.Security.NegoState.StartSendAuthResetSignal(LazyAsyncResult
  lazyResult, Byte[] message, Exception exception)    at
  System.Net.Security.NegoState.StartSendBlob(Byte[] message,
  LazyAsyncResult lazyResult)    at
  System.Net.Security.NegoState.CheckCompletionBeforeNextSend(Byte[]
  message, LazyAsyncResult lazyResult)    at
  System.Net.Security.NegoState.ProcessReceivedBlob(Byte[] message,
  LazyAsyncResult lazyResult)    at
  System.Net.Security.NegoState.StartSendBlob(Byte[] message,
  LazyAsyncResult lazyResult)    at
  System.Net.Security.NegoState.ProcessAuthentication(LazyAsyncResult
  lazyResult)    at
  System.Net.Security.NegotiateStream.AuthenticateAsClient(NetworkCredential
  credential, String targetName, ProtectionLevel
  requiredProtectionLevel, TokenImpersonationLevel
  allowedImpersonationLevel)    at
  System.ServiceModel.Channels.WindowsStreamSecurityUpgradeProvider.WindowsStreamSecurityUpgradeInitiator.OnInitiateUpgrade(Stream
  stream, SecurityMessageProperty& remoteSecurity)    --- End of inner
  exception stack trace --- Server stack trace:     at
  System.ServiceModel.Channels.WindowsStreamSecurityUpgradeProvider.WindowsStreamSecurityUpgradeInitiator.OnInitiateUpgrade(Stream
  stream, SecurityMessageProperty& remoteSecurity)    at
  System.ServiceModel.Channels.StreamSecurityUpgradeInitiatorBase.InitiateUpgrade(Stream
  stream)    at
  System.ServiceModel.Channels.ConnectionUpgradeHelper.InitiateUpgrade(StreamUpgradeInitiator
  upgradeInitiator, IConnection& connection, ClientFramingDecoder
  decoder, IDefaultCommunicationTimeouts defaultTimeouts, TimeoutHelper&
  timeoutHelper)    at
  System.ServiceModel.Channels.ClientFramingDuplexSessionChannel.SendPreamble(IConnection
  connection, ArraySegment`1 preamble, TimeoutHelper& timeoutHelper)
  at
  System.ServiceModel.Channels.ClientFramingDuplexSessionChannel.DuplexConnectionPoolHelper.AcceptPooledConnection(IConnection
  connection, TimeoutHelper& timeoutHelper)    at
  System.ServiceModel.Channels.ConnectionPoolHelper.EstablishConnection(TimeSpan
  timeout)    at
  System.ServiceModel.Channels.ClientFramingDuplexSessionChannel.OnOpen(TimeSpan
  timeout)    at
  System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan
  timeout)    at
  System.ServiceModel.Channels.ServiceChannel.OnOpen(TimeSpan timeout)
  at System.ServiceModel.Channels.CommunicationObject.Open(TimeSpan
  timeout)    at
  System.ServiceModel.Channels.ServiceChannel.CallOnceManager.CallOnce(TimeSpan
  timeout, CallOnceManager cascade)    at
  System.ServiceModel.Channels.ServiceChannel.EnsureOpened(TimeSpan
  timeout)    at System.ServiceModel.Channels.ServiceChannel.Call(String
  action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins,
  Object[] outs, TimeSpan timeout)    at
  System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage
  methodCall, ProxyOperationRuntime operation)    at
  System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage
  message) Exception rethrown at [0]:     at
  Microsoft.Office.Server.Search.Administration.SearchServiceInstance.Synchronize()
  at
  Microsoft.Office.Server.Administration.ApplicationServerJob.ProvisionLocalSharedServiceInstances(Boolean
  isAdministrationServiceJob)
Also Event 6398 shows up every now and then :
The Execute method of job definition Microsoft.Office.Server.Search.Administration.CustomDictionaryDeploymentJobDefinition
  (ID ec00dacf-a390-48ff-a800-05f9678bf768) threw an exception. More
  information is included below. Failed to run flow
  Microsoft.CustomDictionaryDeployment. Correlation Id:
  ed8f429d-8e96-509c-0eb5-1627b4f98499.

I have been trying to resolve these for the last couple of days. But nothing helped.
Just to let you know, I tried adding/resetting the SPN from PowerShell as Administrator using setspn but it says "Insufficient Access Rights to perform this operation" although ideally it should since I am using the privileged account to run this script. Moreover I dont access to have Domain Controller so can not delegate the access rights either.
Please let me know how to resolve this as these 2 errors are filling up my event logs and might be causing the site to go down quite often. 

A:

clearly, it is SPN issue. You have to make sure the SPN properly created.Could you please run the setspn and get list of all SPN which already created.

if you need to allow delegated administrators to configure service
  principal names (SPNs), you must ensure that their user accounts have
  the Validated write to service principle name permission. More
  information, please refer to the link:
  http://technet.microsoft.com/en-us/library/cc731241.aspx

Source
Another thing: 
please check the service accounts of SharePoint Timer Service and SharePoint Search Host Controller service, add a SPN entry for each the service account as the following command:
Setspn.exe -A HTTP/ 
After the above, do an IISREST.

