you update the device on idiotic way: multiple packet instead just only one (on non-SMPIS device)
read all first,
backup the device with both .backup and .rsc and save files outside the rb
save also the inside files you want keep
delete all deletable inside the files folder on routerboard
download
https://download.mikrotik.com/routeros/ ... 6.48.6.zip
and
https://download.mikrotik.com/routeros/ ... 6.49.7.npk
extract from all_packages-mmips-6.48.6.zip only the system, wireless, security and dhcp, files (the others do not matter) and copy only
that on wAP,
on system / package select the button downgrade
when the device is rebooted,
copy routeros-mipsbe-6.49.7.npk inside and reboot with system / reboot
go to system / package and enable all packages, also if you do not use it,
go to system / routerboard and upgrade the bios, if is not already upgraded
reboot the device
copy back the .backup file on routerboard,
on files select the backup and press restore
when rebooted goto system / package / check for updates
select channel stable,
press download & install
and probably you have done.
go again to system / routerboard and upgrade the bios, if is not already upgraded, and reboot.