... as a result, I never get a 404 error. The underlying problem seems to be that a SPIFFS File object does not evaluate as false if it cannot be opened. This diff for [RequestHandlersImpl.h](https://github.com/espressif/arduino-esp32/blob/b92c58d74b151c7a3b56db4e78f2d3c90c16446f/libraries/WebServer/src/detail/RequestHandlersImpl.h#L116) fixes it for me. ```diff 116c116 < if (!f) --- > if (!f || !f.available()) ```