I am trying to connect to my mikrotik via VPN connection from another network but I am not able to create a connection but when I am creating a VPN connection locally it is created. Can someone tell what is blocking my VPN connection to be established from outside. I saw the logs I can see there is a request from outside to connect through VPN so it means I am reaching the router but the connection fails to establish and shows error 800 on my Windows PC. Can someone please tell me if there is anything missing in my configuration? I used the following instructions to create my VPN:

https://rbgeek.wordpress.com/2014/08/26 ... -mikrotik/

By "another network" you mean any NATed private network somewhere in the world but not in your router's location?
Most likely GRE (pprotocol 47) which is essential for PPTP is blocked or that nertwork's router is unable to pass it to your VPN client.
-Chris

Yes another network is at another location not in the same network. I also created a GRE (47) firewall input rule but still still it does not allow me to establish the VPN connection.

Creating the input rule is one thing (which is good).
But does the other router forward GRE?
-Chris

I will solution your problem, but first in outside on windows you can upload photo of error you saw it.

I solved my issue by disabling and enabling the PPTP Server. Thank you all for your support.