Well, I decided to run git reset --hard and rename the SQL database to reinstall the server entirely. Now the only edited files are "renewal.hpp" (uncomment "#define PRERE") and "defines_pre.hpp" (#define PACKETVER 20200401, or other versions depending on the client I'm trying). I set up the conf files:
char_conf.txt
char_name_option: 0
pincode_enabled: no
login_conf.txt
console_msg_log: 3
chars_per_account: 9
use_MD5_passwords: yes
ipban_dynamic_pass_failure_ban: no
inter_conf.txt
login_server_ip: localhost
login_server_id: ---
login_server_pw: ---
login_server_db: ---
login_case_sensitive: yes
ipban_db_ip: localhost
ipban_db_id: ---
ipban_db_pw: ---
ipban_db_db: ---
char_server_ip: localhost
char_server_id: ---
char_server_pw: ---
char_server_db: ---
map_server_ip: localhost
map_server_id: ---
map_server_pw: ---
map_server_db: ---
log_db_ip: localhost
log_db_id: ---
log_db_pw: ---
log_db_db: ---
use_sql_db: yes
The rest just have inter-server login data.
I do get an error in the map server log that to me doesn't seem related to this problem:
[...]
[Status]: Done reading '728' entries in 'db/pre-re/status.yml''
[Error]: Database version 1 is not supported anymore. Minimum version is: 2
[Error]: Failed to verify compatibility with STATUS_DB database file from 'db/import/status.yml'.
[...]
Apart from that no server logs contain any errors.
I'm trying clients 2018-06-20e, 2020-04-01b, 2020-07-15b, 2021-11-03_Ragexe_1635824489 and 2021-11-17_Ragexe_1637052357, downloaded from http://nemo.herc.ws/downloads/#downloadable-exe
WARP gives me no error, but 2020-04-01b is the only one that works without errors - except for the error described in OP and a "There was an error when loading the data account settings. (Please restart to retry.)" in the chat after selecting character, however from what I can find out it's nothing to worry about.
2018-06-20e opens a (game) window that closes immediately before viewing anything,
2020-07-15b opens a white (game) window and an error notification window: "CTwitterDataMgr::CreateInstance()". Upon pressing "OK" (the only option) both windows are closed.
Both 2021 clients give two "Error ExternSettings Value" error popups, after which an error message with garbled symbols (korean characters?), and no game window.
WARP Patches (apart from the recommended) are:
- UnlimitedChatRepeat
- DataFolderFirst
- LoadKrExtSettings
- FixArrowsCharset
- CustomAchieveLub
- CustomTownInfoLub
- CustomPetEvoClnLub
- CustomTipboxLub
- CustomCheckAttLub
- CustomPrivAirplaneLub
- CustomMapInfoLub
- CustomOngQuestInfoLub
- CustomRcmdQuestInfoLub
- EnableSysMenu
- NoLoginOTP
- SkipServiceSelect
- FixHomunAI
- DisConnToLogin
- HideLicense