@supset said in Duetwebcontrol interface not loading after upgrade to 3.1.1:
is the firmware and DWC files located all on the SD card?
firmware is written to the processors internal flash memory, it can be written to the internal flash by usb bootloader. the firmware can also self program by executing M997, in which case it will read the binary firmware from the sd card and write it to the processors internal flash.
the only screenshot that is legible suggest that there is an issue with the content if your sd card, its essentially 404 page, there needs to be an index.htm.gz in /www on the cd card.