We’d like to draw some attention to an issue that was reported (and quickly diagnosed) on our discussion forum last month.
A customer reported that they were no longer able to process received MMS messages using a GSM modem on the Orange network in the UK.
There are a variety of potential causes, such as a SIM not being enabled for MMS support, or incorrectly provisioned Operator MMS settings. However, this case was unusual.
Generally when there is a problem receiving MMS messages via a modem, the first thing we check is whether or not the modem can be used to send MMS messages. Assuming that is OK, we look to see if NowSMS is reporting receiving any SMS messages when an MMS is expected. As described in the How MMS Works article, the initial trigger for MMS message delivery is a specially formatted SMS message known as an MMS Notification.
The MMS Notification message was being received via SMS, and looking at the SMSDEBUG.LOG, it was determined that NowSMS was attempting to retrieve the MMS message using valid settings, but the operator MMSC was returning an error code 412 (Precondition Failed).
Needless to say, a web search for more information on HTTP error 412 Precondition Failed does not offer any good suggestions for what the problem might be.
However, in the discussion thread, Des correctly diagnosed that the MMSC was expecting something in the request that was not being provided, and suggested that the MMSC might be complaining that no user agent profile information is present in the request to retrieve the MMS message.
The solution to the problem was to locate and manually edit the MMSC.INI configuration file, adding the following settings under the [MMSC] section header:
HeaderUserAgent=iPhoneOS/4.2.1 (8C148) HeaderProfile=http://www.apple.com/mms/uaprof.rdf
For additional details, please refer to the original discussion thread: Unable to retrieve mms using nowsms and orange.
For comments and further discussion, please click here to visit the NowSMS Technical Forums (Discussion Board)...