Charaters in incoming message changed automatically

[Kirk Bennett]

I have a system that receives a parameterized message like:
PW@ 12121212 LC@ 9876 TC@ out
It’s been working great for almost 3 years. About 30 days ago the
@ symbol started getting automatically replaced with a dash from some users like:
PW- 12121212 LC- 9876 TC- out
It only happens about 1% of the time but it’s very annoying when the user sent the correct text but they get an error message because my system doesn’t understand the message.
In my receive log it is showing without the @ but with the dash. Could the iSms be doing this? Or do you think the carrier? Or the users phone? I haven’t surveyed yet to find out what phones this happens with.
Any help would be appreciated. Thanks

[Bryon Davis]

Hi Kirk,
If it is only happening 1%, then it is unlikely the iSMS is changing these messages. If possible, I would first verify that the message was sent correctly. Next see if only certain users, phones or carriers are having the issue. If it’s random, then it will be difficult to track down the problem.

Bryon

[Kirk Bennett]

I looked back to what day this problem seemed to start and it was Jan 14, 2015. What’s strange is this was Microsoft’s update day. I don’t see how Microsoft update could cause this problem, unless the carriers servers are MS and something in the update is causing this. That may be why it only occurs sometimes and usually after 1 happens then I get a spurt of more then none for a awhile. Is there anyway to look back to certain dates in the iSms log? I did restart iSms about 10 days ago. Not sure if logs are lost on restart.

[Bryon Davis]

Kirk,
You can see the text the modem received by looking at the SMS Live Log in the Statistics&Logs -> Log Traces menu. When a message is received it comes in as a “+CMT” message. If you are using PDU mode, you may need to use an online PDU decoder to see what the text was.

If the +CMT message shows that it received “-” rather than “@” than most likely it was changed in the Cellular Network(s) before reaching the modem.

If the +CMT message contained a “@”, then check the Inbox to see what is shown there, and also the “Receive API Live Log” to see what message was delivered to your web server.

When you reboot, the logs are wiped, so you would have to wait for it to occur again and then look at the SMS Live Log for that modem.

Bryon

[Kirk Bennett]

PDU is not checked, I don’t even know what that is.
I’ll have to wait until it happens again because everything in the current live log is correct.
I altered my software to accept dashes also. So I’m fine for now.
I was thinking it was something a smartphone was doing but it happened from a guy that has a Motorola flip phone. What happens if someone sends a MMS to the iSms? I’ve never looked and I don’t want to try it and mess something up.
I’ll post if anything changes or I figure out why.

[Kirk Bennett]

I finally captured a “Live Log” item where the “@” symbol is being replaced with a hyphen.
“Live Log” shows:
Feb 17 14:08:39 modem: livelog: [RECV] : +CMT: “1214xxxxxxx”,,”15/02/17,14:08:41-24″,129,4,0,0,”+1xxxxxxxxxx”,145,18
Pw­10106000
Tc­out

“Received Log” shows:
Feb 17 14:08:39 modem: recvlog: [RECV FROM] : 12145555555 : [MSG] : Pw-10106000 Tc-out

[Bryon Davis]

Kirk,
The +CMT message shows that the message is coming from the modem already changed, which most likely means it came from the cellular network already changed. I haven’t seen a case were the modem itself changed characters. I have seen problems when going between different carriers.

Bryon

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