Not Able To Disable Users

I am trying to disable certain users, but it is giving me this error. I am able to disable some accounts, but not all of them. It seems to happen with user that have been recently created.


TITLE: Microsoft SQL Server Management Studio
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Disable Login. failed for Login 'domainuser'. (Microsoft.SqlServer.Smo)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&ProdVer=9.00.3042.00&EvtSrc=Microsoft.SqlServer.Management.Smo.ExceptionTemplates.FailedOperationExceptionText&EvtID=Disable+Login.+Login&LinkId=20476

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ADDITIONAL INFORMATION:

An exception occurred while executing a Transact-SQL statement or batch. (Microsoft.SqlServer.ConnectionInfo)

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Could not obtain information about Windows NT group/user 'domainuser', error code 0x5. (Microsoft SQL Server, Error: 15404)

For help, click: http://go.microsoft.com/fwlink?ProdName=Microsoft+SQL+Server&ProdVer=09.00.3042&EvtSrc=MSSQLServer&EvtID=15404&LinkId=20476


The links lead to a page that is no longer available.

I read somewhere that it had to do with the SQL Server service account and that if you change it to a Domain Administrator it would and it does, but I can not believe the solution. I would say that this even started happening after we applied SQL 2005 Service Pack 2.

Has anyone else seen this problem. Do I really need to make it a Domain Administrator?

Thanks