@jezek i use the same mobile carrier as you in Poland.
I assume that we both cannot properly configure settings that are required by our carrier.
I'm just wondering if there is any chance to check what has been changed in ofono code since Ubuntu Touch.

@sk8rdie you have to remount your file system from read only to read-write

sudo mount -o remount,rw /

If you find solution to fix mms issue please let us know.
I spent few hours changing settings in context files via ofono scripts but i didn't manage to get mms working.

@arubislander That was it! many thanks for this hint
Back to testing. I will keep you updated

@AlainW94 Unfortunately i get the same error

I decided to delete all APNs and create only one APN for internet.
Interesting that this new APN has been created with number 18. Shouldn't be 0 or 1 ? It might be that remove contexts scripts doesn't delete all related data.

phablet@ubuntu-phablet:/usr/share/ofono/scripts$ ./list-contexts
[ /ril_0 ]
    [ /ril_0/context18 ]
        IPv6.Settings = { }
        Password = internet
        Settings = { }
        AccessPointName = internet
        Preferred = 1
        AuthenticationMethod = chap
        Active = 0
        Username = internet
        Protocol = ip
        Name = Internet
        Type = internet

./set-context-property /ril_0 18 AuthenticationMethod pap
Traceback (most recent call last):
  File "./set-context-property", line 62, in <module>
    path = contexts[context_idx][0]
IndexError: list index out of range

I tried to edit mms settings with set-context-property script but either this script doesn't work properly or I'm doing something wrong.
I'm trying to change authentication method from chap to pap. According to my provider i should use pap method.

phablet@ubuntu-phablet:/usr/share/ofono/scripts$ ./list-contexts 
[ /ril_0 ]
    [ /ril_0/context14 ]
        MessageCenter = http://mms.orange.pl
        Username = mms
        MessageProxy = 192.168.6.104:8080
        Name = MMS
        Type = mms
        AccessPointName = mms
        AuthenticationMethod = chap
        Active = 0
        IPv6.Settings = { }
        Password = mms
        Protocol = ip
        Settings = { }
        Preferred = 1

According to the documentation i should use it as it's shown below:
set-context-property [modem] [context_number] <name> <value>

phablet@ubuntu-phablet:/usr/share/ofono/scripts$ ./set-context-property /ril_0 14 AuthenticationMethod pap
Traceback (most recent call last):
  File "./set-context-property", line 62, in <module>
    path = contexts[context_idx][0]
IndexError: list index out of range

Syntax seems to be correct because if i make typo in modem name or context number i get error message that context doesn't exist or modem name is wrong

@AlainW94 That was this thread below:
https://askubuntu.com/questions/413438/no-mobile-data-on-nexus-4-ubuntu-touch

In /usr/share/ofono/scripts i found script create-mms-context so i will try to create mms APN first and then add all parameters with set-context-property script.

@AlainW94 Yes, Wifi is disabled. I do have only one SIM installed. It's not possible to install 2 SIM Cards to One Plus One. It might be that indeed my mms APN is not properly configured due to missing additional parameters. Maybe i could try to add all parameters manually to config file. I've seen some old topic related to Ubuntu Touch where it was described where apn settings are stored

@AlainW94 When i try to open it i get ERR_NAME_NOT_RESOLVED error

@AlainW94 Unfortunately i did those 2 tests (send and receive mms) one after another and because of that the output log from ofono was not really clear.
I decided to perform second test. This time i just sent mms message to my OPO.
Unfortunately there is neither entry in history.sqlite nor attachment in history-service/attachments folder.

New object in attachments folder and new row in history.sqlite is created only when i try to send mms from my OPO to some other device.

Hi Guys,
I followed your instructions and indeed debug mode gave some additional info.
When i try to send mms i get error below

Mar 28 19:41:46 ubuntu-phablet ofonod[1085]: ril_setup_data_call_cb: reply->status for apn: mms, is non-zero: ERROR_UNSPECIFIED

When i send mms to my OPO i get output below so the message is definitely sent to my phone but somehow it cannot be displayed. I found info about those 2 actions in history.sqlite.

ar 28 19:42:45 ubuntu-phablet ofonod[1085]: [0,0147]> RIL_REQUEST_SCREEN_STATE (0)
Mar 28 19:42:45 ubuntu-phablet ofonod[1085]: [0,0147]< RIL_REQUEST_SCREEN_STATE
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,UNSOL]< UNSOL_RESPONSE_NEW_SMS {07918405210077F76404913305000491308291742140790605040B8423F02B06246170706C69636174696F6E2F766E642E7761702E6D6D732D6D65737361676500B487AF848C82986353764D61636E7345484341008D9083687474703A2F2F67656F313A383030322F6353764D61636E73454843410088048102A8BF890B80353038303036393434008A808E03049A42}
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,0148]> RIL_REQUEST_SMS_ACKNOWLEDGE  (1,0)
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,0149]> RIL_REQUEST_SETUP_DATA_CALL (16,0,mms,mms,mms,3,IP)
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,0149]< RIL_REQUEST_SETUP_DATA_CALL {version=10,num=1 [status=0,retry=-1,cid=1,active=2,type=IP,ifname=rmnet1,address=172.28.34.219/29,dns=,gateways=172.28.34.220]}
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,UNSOL]< UNSOL_DATA_CALL_LIST_CHANGED {version=10,num=2 [status=0,retry=-1,cid=0,active=2,type=IP,ifname=rmnet0,address=10.158.51.125/30,dns=194.204.159.1 194.204.152.34,gateways=10.158.51.126] [status=0,retry=0,cid=0,active=-1,type=#002,ifname=IP,address=rmnet1,dns=172.28.34.219/29,gateways=]}
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: Clearing active context; disconnect: 0 active_cid_found: 0 active_ctx_cid: 2
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,UNSOL]< UNSOL_DATA_CALL_LIST_CHANGED {version=10,num=2 [status=0,retry=-1,cid=0,active=2,type=IP,ifname=rmnet0,address=10.158.51.125/30,dns=194.204.159.1 194.204.152.34,gateways=10.158.51.126] [status=0,retry=0,cid=0,active=-1,type=#002,ifname=IP,address=rmnet1,dns=172.28.34.219/29,gateways=]}
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: message repeated 2 times: [ [0,UNSOL]< UNSOL_DATA_CALL_LIST_CHANGED {version=10,num=2 [status=0,retry=-1,cid=0,active=2,type=IP,ifname=rmnet0,address=10.158.51.125/30,dns=194.204.159.1 194.204.152.34,gateways=10.158.51.126] [status=0,retry=0,cid=0,active=-1,type=#002,ifname=IP,address=rmnet1,dns=172.28.34.219/29,gateways=]}]
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,UNSOL]< UNSOL_RESPONSE_VOICE_NETWORK_STATE_CHANGED
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,0150]> RIL_REQUEST_DATA_REGISTRATION_STATE
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,UNSOL]< UNSOL_RESPONSE_VOICE_NETWORK_STATE_CHANGED
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,0151]> RIL_REQUEST_VOICE_REGISTRATION_STATE
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,UNSOL]< UNSOL_DATA_CALL_LIST_CHANGED {version=10,num=2 [status=0,retry=-1,cid=0,active=2,type=IP,ifname=rmnet0,address=10.158.51.125/30,dns=194.204.159.1 194.204.152.34,gateways=10.158.51.126] [status=0,retry=0,cid=0,active=-1,type=#002,ifname=IP,address=rmnet1,dns=172.28.34.219/29,gateways=]}
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: message repeated 3 times: [ [0,UNSOL]< UNSOL_DATA_CALL_LIST_CHANGED {version=10,num=2 [status=0,retry=-1,cid=0,active=2,type=IP,ifname=rmnet0,address=10.158.51.125/30,dns=194.204.159.1 194.204.152.34,gateways=10.158.51.126] [status=0,retry=0,cid=0,active=-1,type=#002,ifname=IP,address=rmnet1,dns=172.28.34.219/29,gateways=]}]
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,0150]< RIL_REQUEST_DATA_REGISTRATION_STATE {registered,0xd0e2,0x390d51f,LTE,(null),20,53474,498,59823391,(null),(null)}
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,0151]< RIL_REQUEST_VOICE_REGISTRATION_STATE {registered,0xd0e2,0x390d51f,LTE,(null),(null),(null),0,(null),(null),1,(null),(null),0,(null)}
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,0152]> RIL_REQUEST_OPERATOR
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,0153]> RIL_REQUEST_SIGNAL_STRENGTH
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,0152]< RIL_REQUEST_OPERATOR (lalpha=Orange, salpha=Orange, numeric=26003)
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,0153]< RIL_REQUEST_SIGNAL_STRENGTH {gw: 99, cdma: -1, evdo: -1, lte: 15 111 180}
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,UNSOL]< UNSOL_DATA_CALL_LIST_CHANGED {version=10,num=2 [status=0,retry=-1,cid=0,active=2,type=IP,ifname=rmnet0,address=10.158.51.125/30,dns=194.204.159.1 194.204.152.34,gateways=10.158.51.126] [status=0,retry=0,cid=0,active=-1,type=#002,ifname=IP,address=rmnet1,dns=172.28.34.219/29,gateways=]}
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: message repeated 3 times: [ [0,UNSOL]< UNSOL_DATA_CALL_LIST_CHANGED {version=10,num=2 [status=0,retry=-1,cid=0,active=2,type=IP,ifname=rmnet0,address=10.158.51.125/30,dns=194.204.159.1 194.204.152.34,gateways=10.158.51.126] [status=0,retry=0,cid=0,active=-1,type=#002,ifname=IP,address=rmnet1,dns=172.28.34.219/29,gateways=]}]
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: [0,UNSOL]< UNSOL_DATA_CALL_LIST_CHANGED {version=10,num=2 [status=0,retry=-1,cid=0,active=2,type=IP,ifname=rmnet0,address=10.158.51.125/30,dns=194.204.159.1 194.204.152.34,gateways=10.158.51.126] [status=0,retry=0,cid=65535,active=-1,type=,ifname=IP,address=rmnet1,dns=172.28.34.219/29,gateways=]}
Mar 28 19:47:13 ubuntu-phablet ofonod[1085]: message repeated 3 times: [ [0,UNSOL]< UNSOL_DATA_CALL_LIST_CHANGED {version=10,num=2 [status=0,retry=-1,cid=0,active=2,type=IP,ifname=rmnet0,address=10.158.51.125/30,dns=194.204.159.1 194.204.152.34,gateways=10.158.51.126] [status=0,retry=0,cid=65535,active=-1,type=,ifname=IP,address=rmnet1,dns=172.28.34.219/29,gateways=]}]```