FTP 150 File Status OK vs 550 File Unavailable
FTP 150 (File Status OK) is a 1xx Positive Preliminary response, while 550 (File Unavailable) is a 5xx Permanent Negative response. 150 indicates that the file status is okay and the server is about to open the data connection for the transfer. This is the normal precursor to a file transfer. In contrast, 550 means that requested action not taken. File unavailable — the file does not exist, the path is wrong, or you do not have permission to access it.
説明
The file status is okay and the server is about to open the data connection for the transfer. This is the normal precursor to a file transfer.
このコードが表示される場合
Right before a file download or upload begins, confirming the file is accessible and the data channel is being opened.
解決方法
No fix needed — this means the transfer is about to start. If the transfer stalls after this reply, check firewall rules blocking the data connection.
説明
Requested action not taken. File unavailable — the file does not exist, the path is wrong, or you do not have permission to access it.
このコードが表示される場合
When you try to download, delete, or navigate to a file or directory that does not exist or is restricted by server permissions.
解決方法
Verify the file path and name are correct (FTP paths are case-sensitive on most servers). Check your user permissions with the server administrator.
主な違い
150 is a 1xx Positive Preliminary response, while 550 is a 5xx Permanent Negative response.
FTP 150: The file status is okay and the server is about to open the data connection for the transfer. This is the normal precursor to a file transfer.
FTP 550: Requested action not taken. File unavailable — the file does not exist, the path is wrong, or you do not have permission to access it.
You encounter 150 when right before a file download or upload begins, confirming the file is accessible and the data channel is being opened.
You encounter 550 when when you try to download, delete, or navigate to a file or directory that does not exist or is restricted by server permissions.
どちらをいつ使うか
For 150 (File Status OK): No fix needed — this means the transfer is about to start. If the transfer stalls after this reply, check firewall rules blocking the data connection. For 550 (File Unavailable): Verify the file path and name are correct (FTP paths are case-sensitive on most servers). Check your user permissions with the server administrator.