Auto It error opening the new projects

Hi there,
After I load a project in AutoIt this error showed up and closed the program. I did some searches on the Internet about this error and nothing that works was found. Any solution ? Why AutoIt gives so many errors ?
Thanks !

AutoIt Error
Line 141 (File “C:UsersPC22Desktop123.au3”):
If GUICtrlRead($checkbox1) = 1 Then
If GUICtrlRead(Error
Error: Variable used without being declared.
