Crash in BP

[Mika]

Hi , i have a question.

When i use ollydbg in some programs says the entry point is not 
the original ,when i attach them they not have problems , but if 
i wanna put a bp in any part of the program, the program crash.


i don't know what i need to learn, is this a unpacking problem ?, 
¿ if is this , how i need to learn to solve ?


thanks for read, and srry for my bad english <3