i have some problem with login in mikrotik by winbox
use mikrotic v 5.7 i can always login to mikrotik by dynamic IPv6 (when I use […] in winbox login window), but not always by IPv4. sometimes it just write “connecting to [IP] (port8291)…”
there was no problems with older version mikrotik (v3x.x and v4x.x)
I need only IPv4
how to fix it?
sorry if this topic was previously, but i cant find it
You mean by mac address right?
no
on screen you can see ROS with IPv6 & IPv4 & Mac addresses
when I truing connect to 192.168.5.x I can’t
when I truing connect to fe80:2x… no problem
but, as I sad, I need only IPv4, why sometimes I cant login be IPv4
Maybe there is something affecting your IPv4 connectivity to the device. Are you on the same v4 subnet and does it have any v4 firewall rules that might affect connectivity?
maybe there is something affecting, but what? subnet is the same, no firewall rules.
if you are on different subnet, even then winbox will display IP address and MAC address, but not allways you will be able to conntect to it.
IPv6 LL address is different
I make screen of my local IP and remote IP
you can see that my IP and remote is in the same subnet
sorry, my IP screen is on russian language 
I use mikrotik only like bridge between interfaces. so I almost have no configurations
you can try to remove locally downloaded plugins and/or un-check load previous session. I have encountered it, and then it resolved itself leaving me in the puddle without memories, that i got a message that windows cannot connect to somewhere.
I found downloaded plugins, removed it and un-check load previous session… no effect
on all of PCs with ROS v5.x is the same problem with login 
anyone?
Based on all the info provided so far and that no-one else has yet to report similar problems, perhaps the issue is something strange on that computer?
Have you tried to connect with another device?