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I have a PPTP connection setup and can not connect. What can I do?
If your PPTP VPN does not connect and shows “LCP timeout”, the connection is being blocked before it can fully establish. In most cases this happens because your router does not allow PPTP traffic properly, or because your internet provider does not give you a real public IPv4 address. You need to check both.
1. Router must support PPTP Passthrough
PPTP uses a special protocol (GRE, protocol 47) in addition to TCP port 1723. Many routers block this by default.
To use PPTP behind a NAT router, your router must support "PPTP Passthrough" and this option also needs to be enabled.
Please ensure that your router supports "PPTP Passthrough" and please ensure it is also enabled. Check your router's manual. If your router has no support for it, you may have to replace it if you require to use PPTP.
2. Check if your ISP is using DS-Lite
If your ISP uses “DS-Lite” (Dual Stack Lite), you do not receive a public IPv4 address. Instead, you get a private IPv4 address that is translated at the provider level (Carrier-Grade NAT).
Please also check if your ISP is running "DS Lite" connection to you. With "DS Lite", users only get private IP addresses that are network address translated at the provider and this is usually incompatible with PPTP. You require a public IPv4 address or switch to a different VPN protocol. Call your ISP and ask for "a public IPv4 address".
1. Router must support PPTP Passthrough
PPTP uses a special protocol (GRE, protocol 47) in addition to TCP port 1723. Many routers block this by default.
To use PPTP behind a NAT router, your router must support "PPTP Passthrough" and this option also needs to be enabled.
Please ensure that your router supports "PPTP Passthrough" and please ensure it is also enabled. Check your router's manual. If your router has no support for it, you may have to replace it if you require to use PPTP.
2. Check if your ISP is using DS-Lite
If your ISP uses “DS-Lite” (Dual Stack Lite), you do not receive a public IPv4 address. Instead, you get a private IPv4 address that is translated at the provider level (Carrier-Grade NAT).
Please also check if your ISP is running "DS Lite" connection to you. With "DS Lite", users only get private IP addresses that are network address translated at the provider and this is usually incompatible with PPTP. You require a public IPv4 address or switch to a different VPN protocol. Call your ISP and ask for "a public IPv4 address".