Does the vector contains data?
To help you more you have to post a debugger log.
For this enable full debugger logging in Settings->Debigger->Common->Enable full log (or something like this)
And then run to your breakpoint, add the desiderate variable and copy the log from the debugger tab from the bottom in code tags here.
You can also try to type in the text field below the debugger log "p VARIABLENAME" and look if the output in the log is correct...
I hope i described the procedure so you can understand, if not ask!
greetings