See Errors in the logs that begin soon after a replication job is started. 

Source: HierarchyRuleManager.ResolveRules
Description: Unable to schedule replication to the specified server (Server: <server.domain>, Exception: System.UriFormatException: Invalid URI: The hostname could not be parsed.
   at System.Uri.CreateThis(String uri, Boolean dontEscape, UriKind uriKind)
   at System.Web.Services.Protocols.WebClientProtocol.set_Url(String value)
   at Altiris.NS.Replication.ReplicationJobHelper.GetWebServiceProxy(String service, ServerReplicationSettings settings)
   at Altiris.NS.Replication.ReplicationJobHelper.GetWebServiceProxy(String service, ReplicationSettings settings, ReplicationEndpoint endpoint)
   at Altiris.NS.Replication.ReplicationJobHelper.GetWebServiceProxy(String service, String urlNS, Nullable`1 timeout, WebServiceCredential credential)
   at Altiris.NS.Replication.ReplicationJobHelper.CreateReplicationJob(String jobId, String name, Guid serverGuid, String serverName, String serverUrl, WebServiceCredential destinationCredentials, WebServiceCredential sourceCredentials, ReplicationRuleCollection rules, ReplicationMode mode, ReplicationPriority priority, Boolean hierarchy)
   at Altiris.NS.Replication.Hierarchy.HierarchyRuleManager.CreateReplicationJob(String jobId, String name, HierarchyNodeItem node, ReplicationRuleCollection rules, ReplicationMode mode, ReplicationPriority priority)
   at Altiris.NS.Replication.Hierarchy.HierarchyRuleManager.ResolveRules(IItem item, HierarchyRuleScope scope, ReplicationMode mode, ReplicationPriority priority, HierarchyRuleCollection rules, HierarchyNodeItem node, Boolean isEvent, Guid hierarchyJobId)).
**CEDUrlStart** :http://entced.symantec.com/entt?product=SMP&version=7.6.1383.0&language=en&module=HiNAcKtQLiKqBeBgjGgb7/VdPrzpknMIRmsaSJ+lAVFtAguGo4tUzSSgig+0uaIB&error=18476440&build=**CEDUrlEnd**

Also see errors when systems check in for Client Configuration Updates.

Unable to get the package codebases for the specified packages from the NS, request: agent = AgentGuid, type = SoftwareDelivery

Invalid URI: The hostname could not be parsed.
[System.UriFormatException @ System]
at System.Uri.CreateThis(String uri, Boolean dontEscape, UriKind uriKind)

The binding for http in IIS had an asterisk (*) in the host name section. This is sometimes used as a wildcard for some applications, but the SMP attempts to resolve the host name specified; and since an asterisk is not a valid host name that can be verified it aborts the replication cycle. 

- Open IIS Manager of the server on which the error was thrown.

- Browse to " Sites > Default Web Site "

- Right-click on Default Web Site and select "Edit Bindings..."

- If the SMP is communicating over http then select "http". If it is using https then select "https". Then select the "Edit" button.

- If there is anything in the "Host name" box, such as an asterisk or anything that cannot be resolved to a valid host name then remove it.