I have experienced this sometimes....I always try several times to enter the code. I have done different things 1) left and gone to another redbox and used the code 2) rented one or two movies using the cc payment. I have been watching movies through redbox for months now and have only paid for movies 4 or 5 times. Only once or twice it was because they couldn't process the codes. There have been several weeks that we had seen so many movies that redbox carried it was had to find any we hadn't seen! LOL I have tried codes 5 times in a row and finally the machine takes it, so try repeated times. All in all this is one of the BEST bargins around and it has been lots of fun finding this website.
How true about renting....the codes get me to the redbox and if I can't find any that work I'll rent one! This is a win win situation for all involved! Thanks for all your work.