You receive an error message when establishing a connection? We have compiled an overview of the most common causes for you.

It is often only minor careless mistakes that prevent success! Be aware of upper case and lower case letters in your username and password.

Error message Cause
421 Too many connections The maximum number of simultaneous connections has been reached. End FTP sessions you no longer need. Some FTP programs - for example FileZilla - can use several connections per FTP session. Check the settings and reduce the number of simultaneous connections/transmissions if necessary.
The specified host is unknown. The FTP server (host) cannot be reached or is unknown. Check your entry. In Web Hosting the server name must correspond to the format - or Example: or If the FTP server is specified correctly, your FTP program may not be able to handle extension as part of the server name. You can still use the program by configuring your own subdomain as an alternative server name.
530 Login authentication failed User name or password incorrect. Forgot your password? Then simply assign a new one.
425 Can't open data connection The FTP connection was established, but no data could be exchanged. A common cause is the use of the FTP program in active mode, which can lead to problems with network components such as a firewall or a router. Activate the passive mode in the settings of your FTP program.
550 Permission denied This error occurs whenever you try to create folders or files in a directory where you have no rights.