Hello
I am using a vpn server with MikroTik OS 5.7
My previous server was 5.5 MikroTik After a few months down the problem
Its My BiG PROBLEM
system error critial router was rebooted without proper shutdown
This problem occurs every few hours
I truly did not matter how I look
Were told that the problem is hardware But I changed my server to another server and bought a data center
But this issue also came up after a few days a new server
I’m sure that’s not a hardware problem and another reason is
Reasons such as an attack on the server, user misuse and vandalism that
help plz:((( 
- Upgrade to v5.12
- Check for power problems, as the error indicates you had a power outage.
tnx 4 answer
Possibly due to attack power to the server is in trouble?
Please Answer I have this problem
What do I have to do? 
Have you upgraded firmware?
You will find under -system - routerboard / upgrade
Reset configuration after upgrade and start a new configuration from scratch.
Same problem here with every version I’ve tried from 5.9 to 5.13 (I’m on dual-core x-86). Went back to 5.6 and so far so good. I do have one machine running OK on 5.12, but others won’t. It’s a mystery to me.
At first we thought it was a power issue too, but changed out UPS and problem persisted. Then we changed version and everything OK. Happens on multiple machine at multiple sites, so it’s not a power issue.
Cam
UPDATE: Still no more problems since downgrading to 5.6