Get MMS working with two german GSM standard 900 MHz SIM cards, manually switch data SIM required

Sailfish OS 4.3 (4.3.0.15) Xperia 10 ii Dual SIM

SIM slot 1 German provider Congstar (100% affiliated company to German Telekom which probably shares relevant part of their infrastructure)
SIM slot 2 German Telekom

Both use D1 network (GSM standard 900 MHz)

Both SIM slots are set to “prefer 4G”, as 3G has been disabled in Germany

SIM slot 2 German Telekom
Data access point
Name “Telekom”
APN name “internet.Telekom”
Protocol “Dual”
Authentication “PAP or CHAP”
User name “telekom”
Password “telekom”

MMS acces point
Name “Telekom MMS”
APN name “internet.telekom”
Protocol “Dual”
Authentication “PAP”, probably “PAP or CHAP” will also work
User name “telekom”
Password “telekom”
Proxy address 109.237.176.193
Proxy 8008
MMS message center „http://mms.t-mobile.de/servlets/mms“

SIM slot 1 congstar
NOTE this configuration is totally different then suggested on the providers home page www.congstar.de

Data access point
Name “congstar Internet”
APN name “internet.Telekom”
Protocol “Dual”
Authentication “PAP”
User name “telekom”
Password “telekom”

MMS acces point
Name “Telekom MMS 2”
APN name “internet.telekom”
Protocol “Dual”
Authentication “PAP”, probably “PAP or CHAP” will also work
User name “telekom”
Password “telekom”
Proxy address 109.237.176.193
Proxy 8008
MMS message center „http://mms.t-mobile.de/servlets/mms“

  1. A working WLAN connection has to be established!
  2. You always have to manually switch the SIM card used for data connection under “Mobile network” to the SIM card slot from which you want to send MMS (but no reboot should be required).

With these settings and procedure i can send MMS from one SIM card to the other one.

This might be of use. Cheers…!

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