SSID for Item with PR_EntryID is null error caused with Pending Items (4279539)

Issue
The following error may be logged in the Shortcut process log file:
2014-07-07 11:56:20Z|WARN|P:5928|T:15|ShortcutProcessorBase|SSID for Item with PR_EntryID [00000000293A15F7D7ECFE47ADE4C1EDA1FBD4BB070090644AB88D5D9748978A1721943A5FAE00000032A979000090644AB88D5D9748978A1721943A5FAE00000032AA9A0000] is null
 
The warning is logged when an Enterprise Vault Shortcut in Outlook is missing a SaveSetID. In most cases this is a “Pending item”.
Note: There may be no pending items in the Watchfile table in the EV SQL database.
 
Solution
You will need to confirm that the item is in fact a pending item. The best way to do this is to check the item properties looking for ArchiveID and SaveSetID. To do this use tools such as MFCMAPI or OutlookSpy. If the item is missing the SaveSetID property, it is a pending item (this can be verified with the Message Class attribute). The pending item/shortcut will point to an item in the source archive and not the new destination archive.
Information on using MFCMAPI or OutlookSpy is in this article.
The next step will be reset the pending item/s in the mailbox and run an Archiving Task on the user’s mailbox; this is in the target environment. After that you will see pending item/s again, but this time the shortcut will point to the target/destination archive.
Information on how to prevent this situation is in this article.