"The server name could not be resolved." error when attempting to restore an archived item through the Outlook Client, while in RPC over HTTP mode.
Could not process the select item.
Reason:The server name could not be resolved.
This error may occur when attempting to access archived items through Outlook while in RPC over HTTP mode. This can be caused by a configuration in the RPC over HTTP setting for Enterprise Vault.
By default, when attempting to access archived items, a call will be made to the Enterprise Vault (EV) Server, through the \Enterprisevault Virtual Directory using the Internal Server name. This is based on settings available in the Exchange Desktop Policy (EV 8.x, 9.x and onward).
Note: For steps on how to configure EV to handle users in RPC over HTTP mode, please refer to the Install and Configuration Guide documentation. Further details are also available per Related Documents.
This error will occur if the following factors are true:
1. In the Mailbox/Desktop Policy => Advanced => Outlook
RPC over HTTP connection is set to Direct.
2. The Internal Server name is not published externally .
3. The company Firewall is not configured to route the Internal Server name from External to Internal.
Set "RPC over HTTP connection" to "Use proxy"
2. In the Mailbox/Desktop Policy => Advanced => Outlook
Set "RPC over HTTP Proxy URL" to a valid External address in the following format:
3. If changes are made to the Policy, perform a Synchronize of the Mailbox Archiving Task for the affected user(s).
4. Confirm the ExternalWebsiteAddress is published externally and a Rule is present on the Firewall to route calls made to this address to the Internal Server name (IE. From http://External.domain.com/Enterprisevault to http://evserver/Enterprisevault)
a. To test this configuration, attempt to access the EV server externally through the external address. If successfully routed internally, a prompt for credentials will occur and access to the EV Webapp home page will load.