Imac - i movie doesn't connect to my camcorder

When i launch imovie, connect my camcorder, try to import files, it doesnt connect, it flags a stripey blue whirly thing stating it is tring to locate my Sony camcorder but then just finishes without connecting

i have rebooted, re-installed imovie and still same issue, I have had no issues before, nothing has been changed.........

Very frustrating.....any ideas folks ?

cheers

Craig