DWC not working after update to 2.0 + 1.21.1

[dintid]

After firmware upgrade I consistently get some java error when trying to connect to web gui. (see image)

My machine were functioning fine and decided to update firmware to newest firmware https://github.com/dc42/RepRapFirmware/releases

I have tried emptying cache. Removed www folder from SD and put in the new again.

Right now I went as far as doing a reset+erase and uploaded new firmware using SAM-BA and reinstalled the firmware files. I've done it twice as I re-downloaded the firmware files to check for corruption..

When using M115 on LCD it displays RepRapFirmware for Duet 2 WiFi/Ethernet Firmware_Version: 2.0(RTOS) Electroniscs: Duet
When using M115 P0 the machine seems to go into some error condition as LED (which is connecte to Duex5) turns off, and some fans turns on..

I can not connect to it using YAT now even though it is displayed as COM4 in my system.

Full screen: It's not listing firmware name or version

[dc42]

Can you try downgrading DWC to 1.21, to see if that fixes the problem?