Symptoms

1. SharePoint SO not returning anything for PeoplePicker column (Claims site)

2. Sharepoint 2010 Worklist Webpart errors with:
Value cannot be null. Parameter name: token

"15500510","2015-10-01 16:06:30","Error","Unknown","8060","ProcessPacketError","SourceCode.Hosting.Server.Services.TCPClientSocket.ProcessMessage","8060 ProcessPacket Error, Authentication With Server Failed : Value cannot be null.
Parameter name: token","system","::1","DLX:C:Program Files (x86)K2 blackpearlHost ServerBin","15500510","aea8d2e598324db2bf50a3b69c1b6871",""

 

Diagnoses

1. Check if the Sharepoint 'Security Token Service' thumbprint matches the thumbprint in the eIdentity].]ClaimsIssuer] table by using Sharepoint Powershell:

(Get-SPServiceApplication -Name SecurityTokenServiceApplication).SigningCertificateThumbprint

2. Perhaps due to hidden/special characters in some of the Identity.Claims configuration table
 

Resolution

Verified that the thumbprint value in the hIdentity].yClaimsIssuer] table matches the Security Token Service thumbprint. When attempting to export the result (to .csv format) for the select queries below:

SELECT * FROM OK2].2Identity].yClaimAudience]
SELECT * FROM OK2].2Identity].yClaimIssuer]
SELECT * FROM OK2].2Identity].yClaimRealm]
SELECT * FROM OK2].2Identity].yClaimRealmIssuer]
SELECT * FROM OK2].2Identity].yClaimTypeMapping]
SELECT * FROM OK2].2Identity].yClaimTypeMap]

It appears that that the columns in the hIdentity].yClaimTypeMap] table were not lining up correctly when opening it in Excel. This indicated the existence of hidden characters (such as TAB, Space, Carriage return and Line Feed eCR]CLF]). Removing the hidden characters for the values in the hIdentity].yClaimTypeMap] table and restarting the K2 service resolved the issue.

Hidden/special characters may exist before/after the values in the following location (for items relating to the Sharepoint Security Token Service):
- >Identity].yClaimIssuer] table: eThumbprint] column
- >Identity].yClaimTypeMap] table: eOriginalIssuer], ]ClaimType], ]ClaimValue] columns

Using Excel or perhaps Notepad with the "Show Hidden Characters" can provide relevant information.