Выкинуть ноутбук и сказать, что украли.

Спустя 10 лет наконец-то смог обновить прошивку на 500-рублёвом роутере TP-LINK TL-R402M. Во всех инструкциях написано просто выбрать файл прошивки и поехали, но роутер принимает имя файла и ip-адрес, т.е. нужно поднимать TFTP-сервер. Но и тут подойдёт не любой, скажем PumpKIN не годится, но с tftpd32 всё наконец-то получилось.
Лог

Connection received from 192.168.1.100 on port 3247 [02/02 20:28:24.968]
Write request for file <r402mv7.bin>. Mode octet [02/02 20:28:24.968]
OACK: <tsize=386548,> [02/02 20:28:24.968]
Using local port 3248 [02/02 20:28:24.968]
<r402mv7.bin>: rcvd 755 blks, 386548 bytes in 1 s. 0 blk resent [02/02 20:28:25.000]
Connection received from 192.168.1.1 on port 1017 [02/02 20:29:04.984]
Read request for file <r402mv7.bin>. Mode octet [02/02 20:29:04.984]
Using local port 3254 [02/02 20:29:04.984]
Ack block 40 ignored (received twice) [02/02 20:29:06.000]
Ack block 40 ignored (received twice) [02/02 20:29:07.000]
Ack block 107 ignored (received twice) [02/02 20:29:10.031]
Ack block 107 ignored (received twice) [02/02 20:29:11.031]
Ack block 108 ignored (received twice) [02/02 20:29:12.031]
File <r402mv7.bin> : error 10054 in system call recv Удаленный хост принудительно разорвал существующее подключение. [02/02 20:29:13.031]
Connection received from 192.168.1.1 on port 1017 [02/02 20:29:24.906]
Read request for file <r402mv7.bin>. Mode octet [02/02 20:29:24.906]
Using local port 3257 [02/02 20:29:24.906]
Ack block 209 ignored (received twice) [02/02 20:29:26.031]
Ack block 209 ignored (received twice) [02/02 20:29:27.031]
Ack block 210 ignored (received twice) [02/02 20:29:28.031]
Ack block 230 ignored (received twice) [02/02 20:29:29.031]
Ack block 230 ignored (received twice) [02/02 20:29:30.031]
Ack block 231 ignored (received twice) [02/02 20:29:31.031]
Ack block 317 ignored (received twice) [02/02 20:29:31.078]
Ack block 365 ignored (received twice) [02/02 20:29:32.109]
Ack block 388 ignored (received twice) [02/02 20:29:34.109]
Ack block 388 ignored (received twice) [02/02 20:29:35.109]
Ack block 389 ignored (received twice) [02/02 20:29:36.109]
Ack block 475 ignored (received twice) [02/02 20:29:37.156]
Ack block 476 ignored (received twice) [02/02 20:29:39.156]
Ack block 476 ignored (received twice) [02/02 20:29:39.156]
Ack block 506 ignored (received twice) [02/02 20:29:40.171]
Ack block 506 ignored (received twice) [02/02 20:29:41.171]
Ack block 507 ignored (received twice) [02/02 20:29:42.171]
Ack block 552 ignored (received twice) [02/02 20:29:43.187]
Ack block 552 ignored (received twice) [02/02 20:29:44.187]
Ack block 553 ignored (received twice) [02/02 20:29:45.187]
Ack block 558 ignored (received twice) [02/02 20:29:46.187]
Ack block 558 ignored (received twice) [02/02 20:29:47.187]
<r402mv7.bin>: sent 755 blks, 386548 bytes in 24 s. 9 blks resent [02/02 20:29:48.312]

Хороший вроттер попался. Мой просто умер спустя 10 лет и я его выбросил.