The ArcTitan server has inbuilt facilities for importing messages from .EML (RFC2822) format, MBOX format, PST format:
EML / MBOX / PST Import
To import messages from .EML (RFC2822) , MBOX or PST format, ensure a volume is available for archiving and then click the Import Data button in the Volumes section of the ArcTitan configuration. Select the import source.
Enter a local source directory and press the Import button.
PST Folder Structures
When importing PST files, ArcTitan will attempt to identify the owner of the PST, so that it can link the folders inside it, to the correct user on the tree view (accessible from Search interface). It achieves this by examining the from addresses associated with Inbox folder messages. If the PST being imported is either flat structured (meaning it has no folders) or there is no Inbox folder, the messages will still be imported (..thus accessible via the Search interface) however they will not be linked to the tree view.
If you wish ArcTitan to import messages recursively, enter “*” in the include directories field.
Missing Folder View
PST file include folder structure data. To view folders in Search, ensure "When Data Available" is selected in Show Tree View field (accessible from Configuration->Search)