Error Message

Could not process the selected items.
Reason: Enterprise Vault is currently unavailable. Try again later.

A dtrace of W3WP from the (EV) Server handling the storage service for the corresponding user's mailbox archive will show the following

(w3wp)  <27460>  EV:L  {CBaseDirectoryServiceWrapper::CreateAndPopulateVaultObjectEx} Number of records [1]

(w3wp)  <27460>  EV:M CAutoAgentsOnline::RequestAction - Successfully Mapped A Task - VaultMachine [ev01.ev.local]|TaskEntryID [13ECBDE352DC7BE4181B9ECDBF1DE751A1012000vault.EV.local.local]|Exchange [..EXCHSVRNOTREQD..]|Mailbox [/o=Veritas Lab/ou=US/cn=Recipients/cn=ABC]|FolderPath []

(w3wp) <27460> EV:L {VaultCreateInstanceRequest::CreateInstance} CLSID [{3342DB60-B74A-11D1-9E4B-0000F8789EA8} (EnterpriseVault.ExchangeArchivingAgentQueue.1)] Server Name [ev01.ev.local] Used Server Name [ev01.ev.local] Num of attempts [1] Total elapsed [0.011s] Result [Success  (0)]

(w3wp) <27460> EV:L    {ClientAuthImpl::RegisterClientToken} Windows token [00000000], Flags [None (0x0)], AuthToken [FRMVLT01.EV.local sr676UL7FA*****]
CAuthHelper::Reset Cancel registration? True CancelId: 25828

(w3wp) <27460> EV:H {ClientAuthImpl::GetLocalAuthServer} (Exit) Status: [Exception]

(w3wp) <27460> EV:L {ClientAuthImpl::CancelClientIdentity} AuthToken [FRMVLT01.EV.local.local sr676UL7FA*****]. Token existed [True]

(w3wp) <27460> EV:M CAutoAgentsOnline::RequestAction - Com Result [0x80070005]

Note: Hex Code 0x80070005 means (Access Denied)

The behavior can be seen when EV Server currently hosting the Archive Task for the corresponding mailbox and the EV Server handling the storage service for the mailbox archive resides on separate servers. If this behavior comes on suddenly it could be a result of security policy settings being implemented. 

Please validate that Authenticated Users and the Vault Service Account (VSA) have Full permissions on the Enterprise Vault installation folder. 

Restart the Enterprise Vault services.