Recently I started using Mikrotik and one of my first task was to start pptp client.
The aim is to unite the two networks. one side is mikrotik- RB1100AHx2, and on the other side TP-LINK TL-R600VPN.
Other router can be only server so Mikrotik must be client.
The launch of the PPTP client was quite easy, with a little reading I was able to link the two networks. So far so good, now the problem:

1. Computers behind Mikrotik have full access to the network of TP-LINK and see all the computers in it, but those other computers can not access my network that is behind Mikrotik.

2. My entire Internet traffic is diverted to another network and I do not want that. The aim is to have only local connection between the two sites.

I use the following information to start the connection: http://vpnonline.pl/en/konfiguracja/mikrotik-pptp


Suggestions?

For example, if your MIkroTik device has 192.168.88.0/24 LAN and you try to reach it from tunnels server side, then sound like you are either missing router for this subnet or you need masquerade rule on server.

... missing route...

Recently I started using Mikrotik and one of my first task was to start pptp client.
The aim is to unite the two networks. one side is mikrotik- RB1100AHx2, and on the other side TP-LINK TL-R600VPN.
Other router can be only server so Mikrotik must be client.
The launch of the PPTP client was quite easy, with a little reading I was able to link the two networks. So far so good, now the problem:

1. Computers behind Mikrotik have full access to the network of TP-LINK and see all the computers in it, but those other computers can not access my network that is behind Mikrotik.

That's easy, you need a rule in the firewall to allow them to see the network.

2. My entire Internet traffic is diverted to another network and I do not want that. The aim is to have only local connection between the two sites.

This time, you need a route pushing your traffic to your gateway, and their traffic to theirs

I use the following information to start the connection: http://vpnonline.pl/en/konfiguracja/mikrotik-pptp

Suggestions?

Why? You could surely setup a simple VPN tunnel without paying for a 3rd party ppoe connection. just point it to the TPlink ip address.

http://www.tp-link.com/en/article-380.html for the TPlink Server
http://wiki.mikrotik.com/wiki/Manual:Interface/PPTP for the Mikrotik Client.

Issue #1:

Your RB1100 gets assigned an IP by the TL-R600VPN. I am going to assume here that the TP-Link just gives a single address to PPTP clients, and doesn't expect other networks to be reachable through it. RB1100 on the other hand, is assigned a route so knows how to reach TP-Link's network.

Issue #2:

Sounds like default route is assigned to PPTP client by TP-Link, hence observed behaviour. Compare routing table on RB1100 with and without PPTP connection to TP-Link.

as for "uniting networks" - why not VPLS or MPLS instead ? :/
so far works fine for me. thats cross-out TP-LINK perhaps, but its make sense anyway.
(but i read that some guys in Poland, Hungary, Indonesia - used it for that too, if i get it/story right)

as for "uniting networks" - why not VPLS or MPLS instead ? :/

That would be overkill for connecting two sites together.

Issue #1:
It can not be made with this type of network.
But we found that with the old router, the network has also been that way and everything work fine for us.
Perhaps in the near future as we take another Mikrotik, we will set up EoIP

Issue #2:
In the tutorial that I have used, the problem was a step 38.
There is Dst. Address 0.0.0.0/0, but I must set here my network (192.168.0.0/24)

as for "uniting networks" - why not VPLS or MPLS instead ? :/

That would be overkill for connecting two sites together.

thats what are VPLS are Perfectly made for.
ie "inter-connecting networks".
as for "overkill" in general, PPTP had more issues, had bigger hardware overhead and severe security issues wouldn't be resolved by few PPTP-improving/maintaining entities, even if its happen in theory.
so, no, generic VPN is "overkill" for that purpose, NOT VPLS or MPLS.

Sure, crack on, see how long it takes you to get two sites connected together with MPLS/VPLS vs. "generic VPN"