Verified answer

Do you know the brand name of the briefcase? If so, look them up on the internet and contact their customer service. or take the briefcase back to the store where you bought it and ask if they know how to reset the combination or have the manufacturer contact info. If you are able to reset the combination...WRITE it down . Also, check the sites below.

Start at 000 and work your way up. There are only a thousand possibilities. At two seconds each, that's about half an hour to try them all.

Locksmith.