Check that the StorageDelete Process is not actively removing data from the Vault Store or Directory DB by Dtracing. If there's no obvious activity on the archives follow these steps.

Example:

253819 11:00:28.844  [4356] (StorageDelete) <3048> EV:L CNTFSStorageDeviceDeleter::BuildExtensionlessSavesetFileName - SavesetIdentifier=[201108113044613~201108030926200000~Z~40938CB249F0E302439A7D8094E688B1], ExtensionlessFileName=[C:\EVStorage\Express Vault Store\Express Vault Store Ptn1\2011\08-11\4\093\40938CB249F0E302439A7D8094E688B1]
253820 11:00:28.844  [4356] (StorageDelete) <3048> EV:L {CNTFSStorageDeviceDeleter::Delete} (Entry) File name=[C:\EVStorage\Express Vault Store\Express Vault Store Ptn1\2011\08-11\4\093\40938CB249F0E302439A7D8094E688B1.DVS]
253821 11:00:28.844  [4356] (StorageDelete) <3048> EV:L {CWORMDeviceHelper::IsWORMDevice:#56} Device [is not] WORM.
253822 11:00:28.844  [4356] (StorageDelete) <3048> EV:L EVCommon::DeleteFile : FileName = C:\EVStorage\Express Vault Store\Express Vault Store Ptn1\2011\08-11\4\093\40938CB249F0E302439A7D8094E688B1.DVS
253823 11:00:28.844  [4356] (StorageDelete) <3048> EV:L {CNTFSStorageDeviceDeleter::Delete} (Exit) Status: [False (0x1)]
253824 11:00:28.844  [4356] (StorageDelete) <3048> EV:L {CNTFSStorageDeviceDeleter::DeleteSaveset} (Exit) Status: [False (0x1)]
253825 11:00:28.844  [4356] (StorageDelete) <3048> EV:L {CSavesetSISManager::DeleteSaveset} (Exit) Status: [False (0x1)]

1. Within SQL Management Studio run the following;

USE EnterpriseVaultDirectory

SELECT *  FROM  Archive

Where ArchiveStatus = 4

This will generate a list of all of the Archives set for Deletion.

2. Check the results and make sure that teh ArchiveName Column contains the Archive/s in question. Take not of the RootIdentity for each Archive

3. Within SQL run the following SQL query to change the status back to Available

6. Refresh VAC and Archive should now be gone, although it may take a few minutes depending on the size of the archive. If in doubt check Dtrace and Archive entry in DB again.