Firmware Name: RepRapFirmware for Duet WiFi
Firmware Electronics: Duet WiFi 1.0
Firmware Version: 1.19alpha3 (2017-05-09)
WiFi Server Version: 1.19-alpha1
Web Interface Version: 1.16

Using an iphone as a hotspot I can connect for a few seconds via DWC, then I get: An AJAX error has been reported….....

08:29 22/05/2017
Last software reset code 0x1001, HFSR 0x00000000, CFSR 0x00000000, ICSR 0x0043380f, BFAR 0xe000ed38, SP 0xffffffff
Spinning module during software reset: Network, available RAM 8868 bytes (slot 4)

08:31 22/05/2017
Last software reset code 0x0031, HFSR 0x40000000, CFSR 0x00008200, ICSR 0x0440f803, BFAR 0x447a0000, SP 0x2001fe5c
Stack: 0041ae99 0041e5b2 81000000 80000000 bfd802a3 e974b355 3facf963 fffffc02 00430121 004334aa 81008a00 000002f3 09c0b000 0042fed2 01000000 2000a540 00000001 00000000
Spinning module during software reset: Network, available RAM 15652 bytes (slot 0)
Error status: 0

08:36 22/05/2017
Last software reset code 0x1031, HFSR 0x40000000, CFSR 0x00008200, ICSR 0x0440f803, BFAR 0x505c0f91, SP 0x2001fe44
Stack: 0041a227 004350a0 21000000 400c0000 200065c8 00000000 0041a343 0041a348 81000000 0000000b 00000000 00000000 ffffffe9 2565c18a 3e05f204 00000000 00430030 000002e2
Spinning module during software reset: Network, available RAM 15652 bytes (slot 1)

Last reset 00:00:22 ago, cause: reset button or watchdog
Last software reset code 0x0031, HFSR 0x40000000, CFSR 0x00008200, ICSR 0x0440f803, BFAR 0x0a9d0a9c, SP 0x2001fe5c
Stack: 0041ae99 0041e5b2 81000000 00000000 ffffffe9 2000a540 00000001 00000001 00000002 2001fee8 0041af53 0041af9a 21000000 00000000 ffffffe9 2000b868 00000001 00000000
Spinning module during software reset: Network, available RAM 15652 bytes (slot 2)

Webserver: rejecting message with: not found

What is not found? Am I missing a SD card file? Everything has been extracted to /www

Also WiFi firmware version reports 1.19-alpha1 not alpha2 but has been upgraded.

Thank you for your continued effort.

Still getting errors and resets, using the latest release

Last software reset code 0x1001, HFSR 0x00000000, CFSR 0x00000000, ICSR 0x0440f80f, BFAR 0xe000ed38, SP 0xffffffff
Spinning module during software reset: Network, available RAM 15956 bytes (slot 0)

HTTP/1.1 500 overflow
Connection: close

I seem to be getting a step closer, at least I can request and get served html404.html

Thank you David for the update, I have got it to work using my iphone as a hotspot, but can not connect it to my works infrastructure (no pages load although I get server response code 200), although the I.T dept. say there are no restrictions in place, I guess they are missing something.
Occasionally I still get disconnections and board resets, here is what M122 outputs:

SENDING:M122
=== Diagnostics ===
Used output buffers: 1 of 32 (2 max)
=== Platform ===
Static ram used: 28556
Dynamic ram used: 79644
Recycled dynamic ram: 2392
Stack ram used: 3680 current, 4504 maximum
Never used ram: 15976
Last reset 00:00:12 ago, cause: power up
Last software reset code 0x0031, HFSR 0x40000000, CFSR 0x00008200, ICSR 0x0440f803, BFAR 0x447a0000, SP 0x2001fe5c
Stack: 0041a479 0041db7e 81000000 2ece0000 40279127 d758f099 bfc253a9 fffffc03 0042f7ad 004327e4 61000200 00008e4e 00000014 00000000 2000a448 00000001 0041f919 00000000
Spinning module during software reset: Network, available RAM 15652 bytes (slot 3)
Error status: 0
[ERROR] Error status: 0

Free file entries: 10
SD card 0 detected, interface speed: 20.0MBytes/sec
SD card longest block write time: 0.0ms
MCU temperature: min 19.1, current 22.1, max 24.2
Supply voltage: min 0.4, current 0.7, max 0.9, under voltage events: 0, over voltage events: 0
Driver 0: ok
Driver 1: ok
Driver 2: ok
Driver 3: ok
Driver 4: ok
Date/time: 1970-01-01 00:00:00
Slowest main loop (seconds): 0.002416; fastest: 0.000032
=== Move ===
MaxReps: 0, StepErrors: 0, MaxWait: 0ms, Underruns: 0, 0
Scheduled moves: 0, completed moves: 0
Bed compensation in use: none
Bed probe heights: 0.000 0.000 0.000 0.000 0.000
Probe change coordinates:
=== Heat ===
Bed heater = 0, chamber heater = -1
Heater 1 is on, I-accum = 0.0
=== GCodes ===
Segments left: 0
Stack records: 2 allocated, 0 in use
Movement lock held by null
http is idle in state(s) 0
telnet is idle in state(s) 0
file is idle in state(s) 0
serial is ready with "M122" in state(s) 0
aux is idle in state(s) 0
daemon is idle in state(s) 0
queue is idle in state(s) 0
Code queue is empty.
Network state is changing mode
WiFi module is trying to connect
SPI underruns 1, overruns 0
WiFi firmware version 1.19-alpha1
WiFi MAC address 5c:cf:7f:37:8b:19
WiFi Vcc 3.11, reset reason Turned on by main processor
WiFi flash size 4194304, free heap 9128
HTTP sessions: 0 of 8
FTP state 0
Telnet state 0
Wifi module is idle

I'm having the same problem, but the web interface page will not load at all.
I am using the most up to date/stable versions of all firmware.

This is what I get from pronterface:

SENDING:M552 S1
WiFi server starting up
DuetWiFiServer version 1.03 (ch fork)
Flash size 4194304, free RAM 32840 bytes, WiFi Vcc 3.11V, host name: duetwifi, reset reason: Turned on by main processor
WiFi server connected to access point P-WIFI, IP=10.236.85.189, signal strength=-58dBm
DuetWiFiServer version 1.03 (ch fork)
Flash size 4194304, free RAM 32840 bytes, WiFi Vcc 3.12V, host name: duetwifi, reset reason: Exception
WiFi server connected to access point P-WIFI, IP=10.236.85.189, signal strength=-58dBm
DuetWiFiServer version 1.03 (ch fork)

It seems like the exception happens a few seconds after requesting a connection.

Any help would be appreciated.

Matthew