Do you have something like a dynamic dns solution? How did you configure your VPN server (and why are you still uring PPTP)? Can you provide all information about your setup, like what is in front of the Mikrotik? Which version of RouterOS are you running? Any logs about this situation?
I do not have anything like a dyndns solution. I also don't use PPTP, I use SSTP and I can set up L2TP as well if that would be better, but all connections come from Windows computers and SSTP served me well so far.
The setup is ADSL modem/router combo which forwards ports and traffic to MikroTik. Mikrotik has a static internal IP set. The routerboard is RouterBoard 951G and runs on 6.37.3.
I will see if anything shows up in logs.
Is your MikroTik router that is behind a changing IP address making connection with another VPN server that has a static address?
Or are you trying to setup a VPN from somewhere else into your MikroTik that is on a changing address?
The first thing should be no problem, as long as you have some dead-link detection on your VPN.
I use L2TP/IPsec in such an environment and the dead link is detected when the IP changes, a new connection is established
automatically. Of course this leads to a minute or so of unavailability of the VPN.
The setup right now is client-to-site. It's Windows computers that are connecting with Mikrotik's VPNs, however updating the connection to site-to-site was my next step. The connecting devices don't have a static IP. I'm not sure that answers your question.