i have rb951-2n and i upgraded it to v6.24
the router became very slow ,cpu usage 100% ,can't make support.rif, profile menu show nothing and the wirlees always disconnect
so i need to downgrade to v6.13
how could i do this and is there any risk in dowgrade this router board????

Try netinstall, it usually corrects such errors. Otherwise there is no specific risk of downgrading if you don't go below the original version from manufacturing.

Upload 6.13.npk to root folder in files.
Then in packages -> downgrade

Upload 6.13.npk to root folder in files.
Then in packages -> downgrade

you mean this files ???

Yes, these files. But select only those you need - check the system-packages what you already have and copy only those.

i have rb951-2n and i upgraded it to v6.24
the router became very slow ,cpu usage 100% ,can't make support.rif, profile menu show nothing and the wirlees always disconnect
so i need to downgrade to v6.13
how could i do this and is there any risk in dowgrade this router board????

Please tell us more detailed about this problem.
What RouterOS you were using before where everything was working?
Are you using regular wireless package or wireless-fp?
Are you using 20/40mhz channel width? If yes, could you try to change it to 20mhz channel-width option and try again?

i have rb951-2n and i upgraded it to v6.24
the router became very slow ,cpu usage 100% ,can't make support.rif, profile menu show nothing and the wirlees always disconnect
so i need to downgrade to v6.13
how could i do this and is there any risk in dowgrade this router board????

Please tell us more detailed about this problem.
What RouterOS you were using before where everything was working?
Are you using regular wireless package or wireless-fp?
Are you using 20/40mhz channel width? If yes, could you try to change it to 20mhz channel-width option and try again?

problem solved thank you and thanks to (jarda-honzam)

but i face another probleme
facebook is too slow and sometimes the page doesn't complete
other websites like youtube,gmail,..... loading fast and complete the page
i think the problem in DNS am i wrong????
NOTE: i use satellite internet ((tooway)) and i can't use OPEN DNS or any DNS service
i can only use google's DNS

Your welcome. You can give us karma if you appreciate our help.

you can enable the DNS Cache on your router and use your router as a DNS server - it could speed up the DNS requests:
http://wiki.mikrotik.com/wiki/Manual:IP/DNS

you can enable the DNS Cache on your router and use your router as a DNS server - it could speed up the DNS requests:
http://wiki.mikrotik.com/wiki/Manual:IP/DNS

doesn't work

Have you corrected DHCP settings to broadcast your router as DNS ?

Have you corrected DHCP settings to broadcast your router as DNS ?

?????
i think i don't