It seems like when your PlayStation 4’s CMOS battery is completely drained, you will lose access to all of your digital library due to a system rule that requires the trophy list to check the internal time.
Once this happens, you will get the standard “An error has occurred with the application.” error with the code CE 34878-0 when you launch any of your digital games.
This was found by Lance McDonald. He shared a tweet stating that the Trophy’s List on the PS4 needs to check the internal system clock if it’s accurate — this internal system clock is the kind of setting that’s hidden from users.
The sole reason for this is to prevent people from dating back their console to make it show like they have unlocked the trophy earlier.
It’s also worth noting that based on the Twitter post, it will also prevent you from starting your disc games as well.
The only issue we see with this “rule” is if there’s no way for the user to change the “internal system clock” manually aside from jailbreaking the console, then this rule is quite irrelevant and has caused issues for a lot of PS4 users.
If you have experienced this, and your PS4’s system battery died, you may need to constantly re-sync and login to PlayStation Network (PSN) to fix the internal system clock every time when you turn on your PS4 until you can get the battery replaced.
Source: PlayStation Universe, Twitter