Hii there, please i am having difficulty upgrading ROS v5.26 with L6 license running on x86 a pc. I get the error “could not resolve address upgrade.mikrotik.com”. Please I would appreciate suggestions such that will help secure license. Thanks
5.26 is out of support from years.
Is not clear what you mean.
Upgrade at least to 6.47.10 downloading the x86 files inside, and reboot
but check first with /system package if you have also user-manager, ntp, etc. because standard upgrade files do not have it,
are in extra package. And do not install extra package on upgrade if you do not have it before
Given its age - i think your better option is to backup the configurations and rebuild it fresh - Given the age I’d say there’s a few steppings you’d likely need to take as latest might not support full conversion from something so old.
If you understand the config enough then I would take the export and rebuild it from fresh install personally.
It’s intriguing that “a wave” of 5.x upgrades have started lately 
http://forum.mikrotik.com/t/recommended-upgrade-path-from-routeros-5-20/150992/6
Perhaps they all got out of prison at the same time! 