So, over vpn everyone is mapped differently? Or is there any consistency there? you can code the linking between the front end and backend.
UNC should work across the board, IF the users are connected.
Updating everyones front end is easier than you think, email out a vbs file link (stored on the network drive) that will copy the front ends to their desktops.
I used to use backends for recording program activity, across 100's of users. The VPN users were always a pain because their append queries took so long that it caused some lost data. Eventually I did a check for a running .exe, if it was there I put remote people on their own backend.
Heres something that might get you started with creating the link in vba.
Code:
Sub CreateDBLink
Dim BackEnd as DAO.Database
on error resume next ' or use an error handler, but it'll do the same thing.
Set BackEnd = CurrentDB.TableDefs("tblLink")
if err.number = 3265 then ' The link wasn't established for some reason, here is where you could put in the vpn backend paths.
docmd.transferdatabase aclink, "Microsoft Access", "Location.accdb",actable, "tblLink"
end if
end sub