Hi.
How to connect users to the server? and Internet access for users via isp2.


Drawing is already ok but still some info might be missing.
Brief answer based on assumptions:
routing.
Add route to server using gateway 192.168.1.100, make sure it has distance lower then what follows here…
Add route to 0.0.0.0 to gateway used for ISP2 (should already be there), make sure distance is higher then previous line.
Lower distance gets preference on routing. With same distance, the most specific one wins (so if both lines are on the same distance, then the line with 192.168.1.0/24 will be chosen over 0.0.0.0/0 since it is more specific)
In case previous was not helping (and probably needed because of those assumptions in first part):
we may need to see config on mikrotik router to determine the correct answer.
in kerio added static routes. Connection established kerio to mikrotik.
no connection mikrotik to kerio. how can i do this

I was referring to your Mikrotik router on the right side.
To be honest, I don’t care about Kerio.
If a packet comes from Mikrotik to Kerio, it should answer automatically using the same way it came in.