For maximum protection, all of them. Each user an be allowed to upload files to their user account. X Cookies Use of cookies to store visitor information so they don't have to fill the information in every time . If their cookies are turned on, the fields which they have filled out in the past will be filled in automatically. Cookies can also be used to scan for duplicate entries.
Winners Define any number of winners .
X Automatic Winner Selection Winners are automatically picked at random once the event expires. The script will even prevent duplicate winners. Can Win Allow all entries or only correct entries to win. X Show Winners on Expire Option to allow the winners to be automatically shown on event expiration and selection. X Email Administrator Option to email event administrator on every entry.