Timeframe panel disappeared

 
Please help. The timeframe panel disappeared. I can not find it. The View--Tools---Periods button is ON. I made new installation on the folder, but no timeframe panel still. Where can I find it? Thanks.
 
Click on menu Window -> Reset to Default.
 
Alain Verleyen #:
Click on menu Window -> Reset to Default.
YESSS...Thanks. (-: