It no longer work through command lines </system package downgrade>. There is still an option in webbox but it wouldn't work either.

kvam64,

downgrade is working fine.. Just tested a rb333, upgraded to rc7, downgraded to rc6, then back to rc7 again.

Upload .npk files for previous version you would like to downgrade to then run /system package downgrade or in winbox you can click system -> packages then click on the downgrade button.

-Gerard

I tried it again but just doesn't work for me. System is not downgraded after restarting (PC).

The packages may be corrupt. Delete all uploaded packages in /files and upload them afresh. Then issue the downgrade command .

Also make sure that you didn't upload the files into one of the hotspot directories/folders. The files will need to be in the root. Also check the log it should tell you why the downgrade didn't work.

-Gerard

can the wrong or currupted version damage the routerboard

you always can try to reinstall routeboard using netinstall tool

edit:

i do not know any such cases when bad version of routeros have damaged routerboard hardware and in testing pre-release version i always have used netinstall if something went wrong.