I'm frequently getting the following in the event viewer.  I've no idea how to address this and could do with some pointers:

7/9/2014 1:28:26 PM
Scheduler Exception 
AssemblyVersion 7.3.1 PortalID -1 PortalName UserID -1 UserName ActiveTabI 

AssemblyVersion:7.3.1
PortalID:-1
PortalName:
UserID:-1
UserName:
ActiveTabID:-1
ActiveTabName:
RawURL:
AbsoluteURL:
AbsoluteURLReferrer:
UserAgent:
DefaultDataProvider:DotNetNuke.Data.SqlDataProvider, DotNetNuke
ExceptionGUID:fe253a7b-cccb-49a1-9e47-efe21553eedf
InnerException:Sequence contains more than one matching element
FileName:
FileLineNumber:0
FileColumnNumber:0
Method:System.Linq.Enumerable.Single
StackTrace:
Message:
System.InvalidOperationException: Sequence contains more than one matching element
   at System.Linq.Enumerable.Single[TSource](IEnumerable`1 source, Func`2 predicate)
   at DotNetNuke.Services.Scheduling.Scheduler.CoreScheduler.GetServer(String executingServer)
   at DotNetNuke.Services.Scheduling.Scheduler.CoreScheduler.LoadQueueFromTimer()
   at DotNetNuke.Services.Scheduling.Scheduler.CoreScheduler.Start()
Source:
Server Name: hvps151

Ken, thanks for responding.

I did try searching, but must have used the wrong terms. Anyhow, I've deleted a duplicate ServerName as suggested by the thread and it appears to have solved the issue.