Agent Tasks which got created for the central gateway are staying in "Pending" status and then change to "expired" after some time,
For Example tasks of type : Deploying client agent , run agentless scans
There appeared to be an error in the Gateway record configuration.
Uninstalling and reinstalling Gateway server (making sure to download an installer linked to the correct OU) and then updating ClientId of the Gateway record in the Database meant that new task were processed successfully by the Gateway server.
-- Get client Id from CI record
select RecId,ClientId,* from CI where Name= 'TTW2K8DIS'
--Check Client Id in Gateway record
select ClientId,* from Gateway
--Correct ClientId on Gateway table
UPDATE gateway set ClientId = '564DA9E3-621029C0-B5872654-DCFC9873' WHERE ClientId = '42277E7E-E4A31980-87509215-410BD931'