You can configure AS2 inbound transfers to move and/or rename files after they are received. These settings, combined with setting Duplicate Contents with different Message ID to Reject will prevent received files of the same name and extension from being overwritten.
To move received files
In EFT Administrator, connect to EFT Server and click the Server tab.
In the left pane, click the user (trading partner) that you want to configure.
In the right pane, click the AS2
Inbound tab.
To specify the folder in which to move all received
files, in the Move received data to folder
box, click the open icon 
. The Browse
for folder dialog box appears.
Click a folder or click Make New Folder to create a new folder, then click OK.
The folder path appears in the Move received data to folder box.
To rename received files
In EFT Administrator, connect to EFT Server and click the Server tab.
In the left pane, click the user (trading partner) that you want to configure.
In the right pane, click the AS2 Inbound tab.
In the Rename file(s) to box, click in the far right
to activate the text box, then type characters and/or variables to change
the name of received files. Use %EVENT.DATESTAMP%
and %EVENT.TIMESTAMP%
to add the date and time to the file name. Use %FS.FILE_NAME%
for the name of the file.
For example, if you type:
%EVENT.DATESTAMP%_%EVENT.TIMESTAMP%_%FS.FILE_NAME%
A file transferred as dailyprogress.doc on May 3, 2008 at 10:56:26 would be renamed to 05032008_105626_dailyprogress.doc.