Outlook Outlook 2007 Backup Tool problem

[AnneMeridian]

I'd been happily using the MS Back-up Tool to automatically backup Outlook 2007, but now t's got stuck! It always wants to download to drive 'E' which happens to be my 3g dongle. Even when I plug in my external hard drive and select it, then save the back-up details it still wants to go to drive E whether the dongle is plugged in or not. I've re-booted the pc but still it won't see the external hard -drive. I've also tried to change it to back up to the laptop's C or D drives but it still sees the E drive. Help!