I have a GL-X750 Spitz v2 and its SMS forwarding stopped working, both email and SMS. I upgraded the firmware to v4.3.25 and tried to enter both a cellphone number and a personalised email address and still errors. The SMS cellphone forwarding said “Unknown error occurred” and when I entered details for my personalised email address and hit Apply, nothing happens. There seems to be no instructions for personalised email accounts (user@customemailaddress.com), and without feedback its hard to know which field was the issue.
My SIM provider’s texts come through to the messages center, so incoming works.
The modem has been quite flakey of late, with lots of stalls and the occasional freeze requiring a reboot. A new page request will show blank for about 30secs then loads. I’ve not touched the settings for at least a year or two and I just updated the firmware from I think v3 to the latest but no improvement. I only noticed the forwarding issue this week, though I think its been an issue for months.
I rebooted the modem yesterday due to a freeze.
nginx/error.log
2026/04/20 19:14:54 [alert] 3647#0: lua_code_cache is off; this will hurt performance in /etc/nginx/conf.d/gl.conf:62026/04/21 18:42:17 [error] 3789#0: *9 lua tcp socket connect timed out, when connecting to 1.1.1.1:53, client: nnn.nnn.8.133, server: , request: "POST /rpc HTTP/1.1", host: "nnn.nnn.8.1", referrer: "https://nnn.nnn.8.1/"cat: can't open '/var/log/nginx/access.log': No such file or directory
system log
Tue Apr 21 18:46:43 2026 daemon.err modem_AT: (modem_AT.c:319) The /dev/ttyUSB2 does not open,continue to try.
Tue Apr 21 18:46:44 2026 daemon.err modem_AT: (modem_AT.c:319) The /dev/ttyUSB2 does not open,continue to try.
Tue Apr 21 18:46:45 2026 daemon.err modem_AT: (modem_AT.c:319) The /dev/ttyUSB2 does not open,continue to try.
Tue Apr 21 18:46:46 2026 daemon.err modem_AT: (modem_AT.c:319) The /dev/ttyUSB2 does not open,continue to try.
Tue Apr 21 18:46:47 2026 daemon.err modem_AT: (modem_AT.c:319) The /dev/ttyUSB2 does not open,continue to try.
Last few lines of kernel.log
[ 126.352860] br-lan: port 3(wlan1) entered blocking state
[ 126.358475] br-lan: port 3(wlan1) entered disabled state
[ 126.364350] device wlan1 entered promiscuous mode
[ 127.552219] br-lan: port 2(wlan0) entered blocking state
[ 127.557815] br-lan: port 2(wlan0) entered forwarding state
[ 131.784038] br-lan: port 3(wlan1) entered blocking state
[ 131.789631] br-lan: port 3(wlan1) entered forwarding state
[11276.263445] usb 1-1.2: USB disconnect, device number 4
[11276.269202] option1 ttyUSB0: GSM modem (1-port) converter now disconnected from ttyUSB0
[11276.277789] option 1-1.2:1.0: device disconnected
[11276.283187] option1 ttyUSB1: GSM modem (1-port) converter now disconnected from ttyUSB1
[11276.291706] option 1-1.2:1.1: device disconnected
[11276.334909] option1 ttyUSB2: GSM modem (1-port) converter now disconnected from ttyUSB2
[11276.343468] option 1-1.2:1.2: device disconnected
[11276.372280] option1 ttyUSB3: GSM modem (1-port) converter now disconnected from ttyUSB3
[11276.380794] option 1-1.2:1.3: device disconnected
[11276.386017] qmi_wwan 1-1.2:1.4 wwan0: unregister 'qmi_wwan' usb-1b000000.usb-1.2, WWAN/QMI device
[11281.175702] usb 1-1.2: new high-speed USB device number 5 using ehci-platform
[11281.371705] option 1-1.2:1.0: GSM modem (1-port) converter detected
[11281.378599] usb 1-1.2: GSM modem (1-port) converter now attached to ttyUSB0
[11281.386689] option 1-1.2:1.1: GSM modem (1-port) converter detected
[11281.393436] usb 1-1.2: GSM modem (1-port) converter now attached to ttyUSB1
[11281.401454] option 1-1.2:1.2: GSM modem (1-port) converter detected
[11281.408291] usb 1-1.2: GSM modem (1-port) converter now attached to ttyUSB3
[11281.416233] option 1-1.2:1.3: GSM modem (1-port) converter detected
[11281.423040] usb 1-1.2: GSM modem (1-port) converter now attached to ttyUSB4
[11281.863570] qmi_wwan 1-1.2:1.4: cdc-wdm0: USB WDM device
[11281.925680] qmi_wwan 1-1.2:1.4: QuectelEC25&EC21&EG91&EG95&EG06&EP06&EM06&BG96&AG35 qmi wwan detected
[11281.936376] qmi_wwan 1-1.2:1.4 wwan0: register 'qmi_wwan' at usb-1b000000.usb-1.2, WWAN/QMI device, ee:a6:f3:b9:91:4f
[11310.718168] do_page_fault(): sending SIGSEGV to dnsmasq for invalid read access from 572e0640
[11310.727292] epc = 55625689 in dnsmasq[55610000+43000]
[11310.732570] ra = 55625621 in dnsmasq[55610000+43000]
[11426.022002] 3g-modem_1_1_2: renamed from ppp0
A reboot fixed it the port /dev/ttyUSB2. I found out the issue with email the SMTP server field, the failure I had had a red box around the SMTP server field which turned out to be a dropdown, but it revealed it needed the server:port pairing. I’ve spent about 40 mins trying different combinations but none authenticate.
The SMS forwarding also fails with message “Unknown error occurred. Please check network environment or reboot the device. I finally found where the AT Command was moved to to check its correct for my SIM company which it is. I get messages to the GLi inbox, so its receiving them and there is nothing in the logs to suggest what the error may be.
I got the cell phone number to stick - it doesn’t need an area code (I wish they’d spell that out) but still not working. All this functioned when I first set it up years ago, though I recalled it took ages as there were inadequate instructions.
This is like a drama in installments. I decided to test the process again after half a day in case there was a slow process behind forwarding and there was. Text forwarding, which I was most interested in, is now working. I really like this modem but you can bury yourself in hours of trying to get basic things working.
Can you tell us which SMTP server you are using? The SMS forwarding is related to the /dev/ttyUSB2 interface, and previous issues may be related it.
Additionally, I recommend using the original power supply or one that‘s at least 12V/1.5A.
Its a personal domain I won’t share, but its difficult from limited logs to work out where the failure occurred, but I’m abandoning testing as its not worth the time.