Hi, I have this problem.
Mikrotik router 951Ui-2HnD with v6.5 OS.
I have a 3,5G USB modem connected to the router's USB port. I have enabled the router to receive SMS.
But after 30 minutes more or less the router is unable to load sms messages that were sent to the phone nr in the USB modem. Therefore I cannot start scripts via SMS. It is a big problem.
Any ideas?

Greetings,
Ahto

Same problem here.

Do you know if this happends in 6.4 as well?

Hello.
I was able to fix this problem: got a brand new gsm usb modem and changed it with the old one.
It was running like two days without any fall backs.

But now I have another problem, print from the log:
gsm, error: unable to load unread sms: cannot open port

It means that the service just brokes down, I mean the "Receive Enabled" is not turned in from some random moment (no tick in the /tool/sms Receive Enabled).
I know that it is turned off automatically when to router reboots, but this has not happened.

I will make a script to automatically put the tick in with 10h interval. I don't like it but there is no other better solution to try.

So my problem (6.4 and 6.5):
Multiple modems, tested with channels 0,1.

The receive-sms just breaks down after about 30 minutes, with the timeout error. I tried scripting around it, but after it disables itself, its impossible to turn it back up.

ros code

[admin@SXT] /tool sms set receive-enabled=yes failure: timeout

So I hoped that something like this would solve it:

ros code

/system routerboard usb power-reset dur=3s :delay 30s /tool sms> set receive-enabled=yes

But with that I get

ros code

/tool sms set receive-enabled=yes action timed out - try again, if error continues contact MikroTik support and send a supout file (13)

I wrote to support last week, of course, no responce.

我有这个系统40英里从我,on a mountain where there is no road. This is currently a MAJOR problem for me

Any solution for error "unable to load unread sms: cannot open port" ?

I changed my RB751U-2HnD, v6.17 to RB951G-2HnD, v6.19, FW: 3.18 and I have this issue now. Errors occur once or twice a day. Modem: ZTE MF636.

On rb751u with s/w 6.17 it worked 100% stable (few months without any error)

same here. (ver 6.32 / 6.29)

I also have it on a 922UAGS-5HPacD with a HUAWEI ME909u-521 modem.
It is working for a few days and suddenly I get it with no reboot. And the worst thing is that it can't be resolved with a reboot. I have to place the sim to a phone remove all sms and then it is back but it is not a solution.
On my last attempt I even used the latest RC 6.37rc20 (I also had it on the stable version 6.36)

Still no way to fix this issue?

If someone comes in handy: I changed the operator (SIM card) and it all worked ...

This fixed it for me: I had the same issue, which was caused by a power failure. Something locked up messages on my sim card and I could not receive new ones. After the power failure all sms messages disappeared from the inbox, but they were still there and visible when I moved the sim card to another router with a different gsm modem. The following steps kind of unlocked the sim card and I can now receive messages again:

1. open up serial terminal on ROUTER OS

2. delete all messages with AT command

For your reference:https://m2msupport.net/m2msupport/atcmg ... -messages/

For me the issue was fixed by specifying "channel2" instead of channel 0 in the SMS settings. GSM log is more chatty now and I get zero timeouts. Swapping SIM cards didn't help at all.
The only issue is that after each reboot you must go to SMS settings in Webfig to "activate" the modem, otherwise it won't be receiving anything. It can probably be done in console somehow, perhaps by sending some (any?) AT command to the modem, but I haven't figured that out yet.