Error while running Profile synchronization (Event ID: 6398)

Question

Hi,
We had our User Profile Synchronization service in stopped state for quite some time due to our SQL server having "Named Instance". Since RTM version had this compatibility issue, I patched my farm with SP2 + FEB 2014 CU.
Now the "User Profile Synchronization Service" is running (I started it and now it was a success). However when I start the Profile sync job (either INC or FULL), it fails. This is the error I get:
The Execute method of job definition Microsoft.Office.Server.UserProfiles.UserProfileImportJob (ID c10650ed-0935-47a5-b3ce-a307c576ad9a) threw an exception. More information is included below.
Operation is not valid due to the current state of the object.
Log Name: Application
Source: Microsoft-SharePoint Products-SharePoint Foundation
Date: 6/25/2014 3:47:16 AM
Event ID: 6398
Task Category: Timer
Level: Critical
Keywords:
User: ST\sps02-svc
Computer: EMEA-MOSS1.st.stroot.local
Description:
The Execute method of job definition Microsoft.Office.Server.UserProfiles.UserProfileImportJob (ID c10650ed-0935-47a5-b3ce-a307c576ad9a) threw an exception. More information is included below.
Operation is not valid due to the current state of the object.
Event Xml:
<Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
<System>
<Provider Name="Microsoft-SharePoint Products-SharePoint Foundation" Guid="{6FB7E0CD-52E7-47DD-997A-241563931FC2}" />
<EventID>6398</EventID>
<Version>14</Version>
<Level>1</Level>
<Task>12</Task>
<Opcode>0</Opcode>
<Keywords>0x4000000000000000</Keywords>
<TimeCreated SystemTime="2014-06-25T03:47:16.577398600Z" />
<EventRecordID>484089</EventRecordID>
<Correlation ActivityID="{A6F9E131-4925-4889-A759-5F873C4B2E74}" />
<Execution ProcessID="9140" ThreadID="7372" />
<Channel>Application</Channel>
<Computer>EMEA-MOSS1.st.stroot.local</Computer>
<Security UserID="S-1-5-21-1058282146-1732951074-3797079023-18290" />
</System>
<EventData>
<Data Name="string0">Microsoft.Office.Server.UserProfiles.UserProfileImportJob</Data>
<Data Name="string1">c10650ed-0935-47a5-b3ce-a307c576ad9a</Data>
<Data Name="string2">Operation is not valid due to the current state of the object.</Data>
</EventData>
</Event>
Here are the observations:
- User Profile Synchronization Service - Running
- User Profile Service - Running
- Both FIMS - Running
- On User Profile Service Application page, I see "User Profile Sync is not currently provisioned."
- If I go in for "Configure Sync Connections" I see --- The query returns nothing. 
- On clicking "Create new connection" I get this error:
What could be wrong now?

Answer 1

Clear the file system cache on all servers in the server farm on which the Windows SharePoint Services Timer service is running. Please refer to the following link:
http://ahmedmadany.wordpress.com/2011/05/08/user-profile-service-an-update-conflict-has-occurred-and-you-must-re-try-this-action/
Make sure that the SharePoint Farm account, which is created during the SharePoint Farm setup, is a member of the local Administrators group where the User Profile Synchronization service is deployed.
Make sure that the SharePoint Farm account is able to log on locally on the server where User Profile Synchronization is deployed.
More information are provided in the link below:
http://www.sysadminsblog.com/microsoft/user-profile-service-an-update-conflict-has-occurred-and-you-must-re-try-this-action/
http://www.sysadminsblog.com/microsoft/event-6398-microsoft-sharepoint-administration-spsqmtimerjobdefinition-exception/
If this helped you resolve your issue, please mark it Answered