Error while VI Compile

I designed VI successfully...there is no error....there is no broken symbol on VI ...so Every thing is fine.

But when i went to save it ......i received one error  i.e.VI failed to compile....also observation broken symbol on VI.....

But i could not find the reason for it.

Should guide me to resolve it...or what will be the reason....

I have one concern  which may be reason.....Suppose i have taken one Indicator terminal out from SubVI ..but i have not used it....i keep it free...not used

...do you feel it could be reason or anything else  ?

Thanks in Advance.