What database are you using ?
if you are using SQL database please run below query and find sep client status.
See SebastianZ below articles
https://www-secure.symantec.com/connect/articles/compilation-sql-queries-sepm-database
SEP Client ID information contains:
♦ SEP computername
♦ Client ID, Computer ID, Hardware ID
♦ Client Status
♦ Client creation and last update timestamp
♦ Operating System information
♦ SEP Client Version
SELECT [Comp].[COMPUTER_NAME]
, [Agent].[DELETED]
, [Agent].[CURRENT_CLIENT_ID]
, [Comp].[HARDWARE_KEY]
, [Comp].[COMPUTER_ID]
, dateadd(s,convert(bigint,[Comp].[TIME_STAMP])/1000,'01-01-1970 13:00:00') as Time_Stamp
, [Agent].[STATUS]
, dateadd(s,convert(bigint,[Agent].[CREATION_TIME])/1000,'01-01-1970 13:00:00') as Creation_Time
, dateadd(s,convert(bigint,[Agent].[LAST_UPDATE_TIME])/1000,'01-01-1970 13:00:00') as Last_Update_Time
, [Comp].[OPERATION_SYSTEM]
, [Agent].[AGENT_VERSION]
FROM [dbo].[SEM_AGENT] as [Agent] inner join [dbo].[SEM_COMPUTER] as [Comp] on [Agent].[COMPUTER_ID]=[Comp].[COMPUTER_ID]
/* where [Comp].[COMPUTER_ID] like 'Computer ID as used in the database' */
/* where [Comp].[COMPUTER_NAME] like 'NetBIOS name of computer' */
/* where [Agent].[CURRENT_CLIENT_ID] like 'Unique ID as displayed on General tab of client properties in console' */
order by [Comp].[COMPUTER_NAME] asc