End-User Experience The Update Channel Thumbnail feature allows the KMS Channel Manager to choose and set a thumbnail for a channel.
If there was no media, the thumbnail was based on the type of channel (open, private, moderated, shared repository).
This can happen because a program or system crash interrupts the database in the middle of a crucial operation, but database corruption sometimes happens for no apparent reason.
Fortunately, Apple provides a repair mode for i Photo, but you won't find it in any menus or toolbars.
Question: My copy of i Photo is starting to show generic placeholder icons for some of my events (the correct photos are still inside each one so far, though). For this, you can blame the digital disease of database corruption.
Watching the application that keeps a decade's worth of photos threaten to decay into the electronic equivalent of a disorganized shoebox can unsettle any amateur photographer — just look at the panicked posts about this in Apple's tech-support forums.