F-SECURE ANTI-VIRUS FOR MICROSOFT EXCHANGE 7.10 Administrator's Manual page 291

You should be able to release, reprocess or download quarantined
messages and attachments when at least one node of the cluster is
currently online. However, as the clustered Exchange 2007 can have the
mailbox role only, you need to configure the hub transport role and
mailbox role servers so that quarantined messages can be delivered.
Hub Transport Role Server:
1. Share the Pickup folder on the Exchange Hub Server. By default, the
Pickup folder is located at %Program Files%\Microsoft\Exchange
Server\TransportRoles\Pickup.
Use the default name (Pickup) for the share so that it can be
accessed at \\HubServerName\Pickup.
2. Right-click the Pickup folder and select Properties > Sharing and click
Permissions. Assign Read and Change permissions to the Pickup
folder for the Exchange Servers group or for the Mailbox Role
Servers directly.
3. Go to the Security tab and assign all the permissions except
FullControl and Special for the Pickup Folder.
Mailbox Role Server
1. Open the Windows Registry Editor and go to
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\FS
AVMSED\Parameters subkey.
If the Parameters subkey does not exist, create it.
2. Under the Parameters subkey, create PickupFolderPath string value
that points to the Pickup Folder share of the hub server that has been
created earlier (\\HubServerName\Pickup).
The registry value has to be changed on all cluster nodes.
After these steps have been completed, the quarantine works properly on
the Mailbox Role only servers as well.
You do not have to reboot or restart the server, the product takes
the new settings into use automatically.
APPENDIX C
Deploying the Product on a Cluster
291