This log prints bind information and packet transactions. The following line is an example of a successful bind request.
9-8-2011 13:2:36|0|TranslatePDU|+INF: 00000000:80000009:SMSC
The following lines are example of bind failure for wrong entry of user account in “conf.ini” file.
9-8-2011 13:12:3|0|TranslatePDU|+INF: 0000000D:80000009:SMSC
This log prints “heart beat” information after every span of heart beat delay (in sec) which is defined in 27th line of conf.ini file. For example, if the heart beat delay is configured as 20, this file will write several lines of information after every 20 seconds.
This log prints the information about the SMS to be updated into “smsoutbox” table. For example, the following lines will be printed at the time of insertion of SMS into “smsoutbox”.
9-1-2011 2:0:12|2|UpdateOutContent|Message Found: Dear User, the keyword you sent is not correct. Please type correct keyword and send to 3678. 
This log prints information of Submit SM. For example, the following line is an example of successful submission.
9-8-2011 13:14:39|3|SubmitSM|+OK: Submit SM Successful
The following line is an example of failed submission.
9-8-2011 13:14:39|3|SubmitSM|-ERR: Socket Closed..!!
This log is updated whenever any SMS is received and inserted into “smsinbox” table.
This log is updated whenever any SMS is delivered to user from “smsoutbox” table.
The probable reason is Connectivity failed or bind failed. See log “DDMMYYYY-0000.txt” and take steps accordingly.
The probable reason is database failure. See “DDMMYYYY-Receive.txt” log to find out the problem and take steps accordingly.
The probable reason is IIS may be down, or mysql may be down.
The problem is in operator side, communicate with operator.
See reason code from SMPP protocol spec and take steps accordingly.
The probable reason is Application is down.
One of the main reasons can be – SendSMS web service is wrongly configured.
You can check the smsoutbox table for the desired SMS. If you can find your SMS in the table then check the SMS Status. If the SMS Status is QUE with retry count more than 1, wait until SMS is in FAILED status. If the SMS is in FAILED status, you can see the reason code in the table. Then check SMPP Protocol specification document for the Reason Code description and solve accordingly. Mostly the Source or Destination Number formats are to be corrected.
If the SMS is not found in smsoutbox then you can be sure that SendSMS web service is not correctly configured (may be not with the active SMS GW).
One reason can be the csv file is not correctly formatted.
Another reason may be the “CSV” folder in “smsgateway” folder has not write permission. Check the permission status and give permission to everyone for this folder.
This may be for wrong combination of keyword and short code in database.
Check the “keyword” table first if the ShortCode and keyword pair is correct as expected.