Breakpoints disabled automatically while debugging

Hi ,

           I am using CCS v5.2.1.00018 .I am trying to place breakpoint  at a certain line in my code.But when I debug the code using MSP-FET430UIF, these breakpoints are disabled .I have tried placing breakpoints before and it worked fine.I am facing such type of problem for the first time.Is there any settings that I need to do to avoid this situation?

Thanks in advance,

Smita P