Does anyone know what's this error message all about? i can't install keynote... thanks in advance.
down load in safe mode:
shut down the Mac
start the Mac again,
immediatly after the chime sound, press the shift key untill gray Apple appears
it will take much longer to boot, let it procede in its own time
when fully booted, loginto App Store and try the download again
when downloaded restart normally
Retrieving data ...