I messaged Paige about this, who informed me that disk space was running critically low, and she deleted some log files in C:\inetpub\logs\LogFiles\W3SVC1
This temporarily fixed the problem, but the disk space is still running critically low. I ran Disk Cleanup, but that only temporarily fixed the issue. I installed DataDog to better monitor the disk space on the C: drive – currently at 500mb free – and I am starting another incident to investigate this problem further.