For macOS 10.15 (Catalina): The PPTP library was removed from the macOS kernel.It is a Universal app for both Intel Macs and Apple Silicon M1 Macs running Big Sur.
At this time, the only working solution we could find is the VPN Tracker 365 (pre-release version). Important! Taking into account that are no free and working solutions for setting up PPTP on Macs running Big Sur and Catalina, you may take into consideration setting up PPTP on a router and connect your Mac to it on cable or WiFi.
It also explains why PPTP is no longer supported on macOS starting from version 10.12 (Sierra) and what are the alternative solutions to set up PPTP VPN on Mac. This short tutorial helps you set up a PPTP VPN connection on your Mac.
