Why are all my apps now force closing after updating to android 8?

[Android Central Question]

None of the apps are running for more than a few seconds before the system shows a window stating that the app was forced to close.

Phone - Samsung Galaxy A8

 

[Rukbat]

That sounds like a cache problem. Restart into recovery* and wipe the cache partition (not the data/system, just the cache). Then reboot the system.

*
Turn off the phone by holding the Power key for a short while, then choosing Power Off.
Press and push Volume Up + Power button together for a couple of seconds until the phone starts.
Release all buttons when the Samsung Logo shows up.
If Android logo with "No command" appears, tap Volume Up + Power again.
Wait for the recovery menu.

Use the volume keys to go up and down, the power button to choose the currently highlighted item.