Can't open data connection error.
Problem
425 Can't open data connection error
Cause
The 425 error means that the data channel is blocked or closed between you and the server you are trying to connect to.
Solution
- For Active connections open ports 20 and 21
- For Passive connections open ports 21 and 1024+ (and higher)
If a successful connection cannot be established, check all devices that are between the client and server to ensure that the proper ports are open (e.g. routers).