The software lets you save your work periodically when you're entering a new listing. To save what you've entered so far, in the listing input form click one of the Save buttons, which are along the right side of the form. After a moment, you can continue entering your listing information.
If you cannot finish entering a listing for some reason, and want to leave the form, click the Save Listing as Incomplete and Exit button. Later, you can finish your incomplete listing.
NOTE: The Session Timeout feature is disabled when you're entering a new listing, or modifying an existing one (from the Listing Information form). If you have partially entered a listing and have to leave your computer for some reason, your MLS session will not expire.
See also