Hi, i created a VPN conection in my mikrotik router. I successfully conected my Win seven to the VPN and i can access to all the services, rdp, shared folders... but i can't acces to any linux host, i do not receive any response making ping to those hosts. i need to connect via ssh to my elastix server, but i do not have even ping. If i open a terminal in winbox i do receive response making ping to elastix server, but from outside over VPN i do not. What could be the problem?

It should work. I am connecting many linux hosts via Mikrotik VPN.
Assumed: You(Win7) ------> Miktotik(thro VPN) -----> Linux Host. right?

Some how i can judge where the issue will be... please check assigned ip addr (for pptp tunnel in win7) may be blocked or no route to your Linux host.
Or in other way you can test by assigning another temporary IP( which was accessible) to your Linux host.

Yes, it's right. My mikrotik network adress is 192.168.0.0/24 and the ip for pptp tunel is 10.0.0.1/24 and 10.0.0.2/24. I thought that was not required that the pptp was in the same subnet, so i asigned diferent adresses for the local and the pptp network. That worked fine for windows hosts, but not for linux hosts. I solved it putting the pptp network under the same subnet that the local network with the adresses 192.168.0.200 and 192.168.0.201 at the other side of the tunnel, and setting up in bridge interface the proxy-arp. If i just set up the proxy-arp with the pptp network in other range, it does not work, i do not obtain response making ping to any host windows or linux. By other side if i just put the pptp network in the same subnet that the router without setting up proxy-arp in bridge, it does not work neather. I had to make both changes. I do not know why, but that worked... anyway, i do not understand why windows hosts works fine with the pptp tunnel in other subnet and the proxy-arp disabled but not the linux hosts.

I'd check routing configuration on linux hosts. Could be that to access some subnets, your MT is not used as gateway?