A person can perform the re-marriage after their divorce in these conditions - 

He/She has got the divorce decree from the court such that -

1) Another partner has no right to appeal against the decree or,

2) If the other partner has the right to appeal,  the time period for appeal has failed or,

3) Another partner has filed an appeal in court but it has been dismissed.

In these situations, the person can marry once again after the divorce decree.