Select the Defer breakpoint check box from within the Line Breakpoint dialog if you want to set a line breakpoint in a DLL that is not currently loaded.
When a DLL in which you have set a deferred breakpoint is loaded, the breakpoint state changes from deferred to active. When the DLL is freed, the breakpoint state changes back to deferred.
If you enter an incorrect source, file, or line number, the debugger will be unable to activate the breakpoint when the DLL is loaded, and the breakpoint will remain in the deferred state.
Note: You cannot set a deferred breakpoint in a preloaded DLL, but you can set one in a program that has some preloaded DLLs and some dynamically loaded ones.