These changes are made specific to the user in the registry. The DWORD values in hex are located as follows:
Autosave Time (default 3 minutes):
Autosave Location (default Drafts):
For the SAVE_LOC for drafts, there are four options with their decimal DWORD values:
5 Sent Items
While the defaults should be suitable for more, there is some control for others who may work with Outlook 2007 a little differently.