how to solve this

Depending on the project and how many are in the group, Break it down and assign everyone a diffrent job to complete or role to play in the project. When everyone else finishs they'll all be waiting on the person not cooperating to finish, 9 out of 10 times everyone will become angery at him and peer presure will compale to either do his part of the project or others will start to complaine about him to the teacher;)

i was once in a situation like yours. what i did was we did our project as planned. but we didn't mind or included the other member who didn't cooperate. when the deadline of submission came, we submitted our project together with a report about a group member who didn't cooperate. it's unfair to the other who helped and work hard for the success of the project. the irresponsible member got what he deserved.