/etc/config/network
config interface 'wan'
option ifname 'eth1'
option proto 'dhcp'
config interface 'vpn'
option proto 'pptp'
option username 'client'
option password 'password'
option server 'pptp-server'
opkg list for pptp
kmod-nf-nathelper-extra - 4.9.120-1
ppp-mod-pptp - 2.4.7-12
logread
Fri Dec 14 10:29:21 2018 kern.info kernel: [ 4893.656167] pptp-vpn: renamed from ppp0
Fri Dec 14 10:29:21 2018 daemon.info pppd[12346]: Using interface pptp-vpn
Fri Dec 14 10:29:21 2018 daemon.notice pppd[12346]: Connect: pptp-vpn <--> pptp (pptp-server)
Fri Dec 14 10:29:42 2018 daemon.warn pppd[13109]: Result code is 2 'General Error'. Error code is 0, Cause code is 44048
Fri Dec 14 10:29:51 2018 daemon.warn pppd[12346]: LCP: timeout sending Config-Requests
Fri Dec 14 10:29:51 2018 daemon.notice pppd[12346]: Connection terminated.
I have tp-link 740 v4 and have been trying to configurate pptp. Unfortunately do not find any solution