CompleteFTP error messages, and what each one means

Exact error messages produced by CompleteFTP, and the article that explains each one. Messages are reproduced verbatim, so searching this page for the text in front of you should find it.

Some messages have more than one cause and appear against more than one article. Where that happens, every article is listed and each says how to tell which case you have.

152 messages from 12 articles.

Message Explained in
431 Server error Why an SSL certificate won't import into CompleteFTP, and how to fix it
AD/Windows group names may not contain the following characters: Using Active Directory, Entra ID (Azure AD), SAML and LDAP groups to control who can log in to CompleteFTP
Admin CLI not enabled. How to enable Debug logging in CompleteFTP for troubleshooting
An error occurred during the creation of the configuration file. CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
An error occurred while generating the configuration file. CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
An error occurred while getting the list of Windows users from the server. Using Active Directory, Entra ID (Azure AD), SAML and LDAP groups to control who can log in to CompleteFTP
An existing configuration containing a production license was detected. CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
An internal error occurred when the certificate was being saved to the configuration (private key lost). Why an SSL certificate won't import into CompleteFTP, and how to fix it
Authenticated with partial success SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
Auto-banning disabled for IP filtering and whitelisting in CompleteFTP: what it supports and how to configure it
Can't open data connection. Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
Certificate file doesn't include private key, so this must be supplied separately Why an SSL certificate won't import into CompleteFTP, and how to fix it
ChannelDataWindow is stopped Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it
CompleteFTP Manager failed to start CompleteFTP service CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
Configuration File Creation Error CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
Configuration file does not exist at How to export and import CompleteFTP configuration between servers and versions
Connection abruptly closed: An established connection was aborted by the software in your host machine CompleteFTP: System.OutOfMemoryException during SFTP, or a service that stops responding
Connection timed out after 20 seconds of inactivity Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
ConsumeWindowSpace (32768) timed out Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it
ConsumeWindowSpace timed out Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it
Could not decrypt key. Please check the password. Why an SSL certificate won't import into CompleteFTP, and how to fix it
Could not load certificate Why an SSL certificate won't import into CompleteFTP, and how to fix it
Could not load file or assembly 'edtFTPnetPROSTD Does edtFTPnet/PRO support .NET 8? Which assembly to reference for .NET Framework, .NET Core and .NET 5+
Current config version: How to export and import CompleteFTP configuration between servers and versions
Denied connection on port IP filtering and whitelisting in CompleteFTP: what it supports and how to configure it
does not have permission to change into home directory: Using Active Directory, Entra ID (Azure AD), SAML and LDAP groups to control who can log in to CompleteFTP
does not match the version of the server software CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
due to auto-ban IP filtering and whitelisting in CompleteFTP: what it supports and how to configure it
SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
ECDHE_ECDSA certificates not supported Why an SSL certificate won't import into CompleteFTP, and how to fix it
Entering Passive Mode Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
EnterpriseDT.Net.Ftp.Ssh.SFTPException: ConsumeWindowSpace timed out Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it
ERROR ChannelDataWindow Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it
Error opening configuration file How to export and import CompleteFTP configuration between servers and versions
Error while loading config from CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
Error while starting server CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
Exception thrown in packet processing CompleteFTP: System.OutOfMemoryException during SFTP, or a service that stops responding
failed - trying next plugin Using Active Directory, Entra ID (Azure AD), SAML and LDAP groups to control who can log in to CompleteFTP
Failed to bind port Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
Failed to connect to 127.0.0.1:14983 within timeout 120000 ms CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
Failed to find certificate's private key. Error: -2146885621 Why an SSL certificate won't import into CompleteFTP, and how to fix it
Failed to load certificate with private key Why an SSL certificate won't import into CompleteFTP, and how to fix it
Failed to load server certificate: Access is denied. Why an SSL certificate won't import into CompleteFTP, and how to fix it
Failed to retrieve directory listing Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
Failed to send status message Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it
Failed to start service: CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
failed to verify RSA (multi) SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
Failed to verify signature: RSA public key not set for user SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
File opened that is not a database file How to export and import CompleteFTP configuration between servers and versions
found but not available on site SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
further authentication required SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
has no SSH services enabled SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
home directory does not exist SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
Host not found: IP filtering and whitelisting in CompleteFTP: what it supports and how to configure it
If a certificate is specified, it must have a private key. Why an SSL certificate won't import into CompleteFTP, and how to fix it
Increased window space by Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it
Index was out of range. Must be non-negative and less than the size of the collection. Why an SSL certificate won't import into CompleteFTP, and how to fix it
Invalid data and/or password Why an SSL certificate won't import into CompleteFTP, and how to fix it
Invalid IP address/host-name: IP filtering and whitelisting in CompleteFTP: what it supports and how to configure it
Invalid logging level: How to enable Debug logging in CompleteFTP for troubleshooting
Invalid value, How to disable weak ciphers and encryption algorithms in CompleteFTP
is already using port CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
is not a member of any allowed AD groups. Using Active Directory, Entra ID (Azure AD), SAML and LDAP groups to control who can log in to CompleteFTP
Key not valid for use in specified state Why an SSL certificate won't import into CompleteFTP, and how to fix it
Keyset does not exist Why an SSL certificate won't import into CompleteFTP, and how to fix it
LDAP query pattern must contain a username placeholder. Using Active Directory, Entra ID (Azure AD), SAML and LDAP groups to control who can log in to CompleteFTP
License owner and/or key not found. Please set the LicenseOwner and LicenseKey properties. Does edtFTPnet/PRO support .NET 8? Which assembly to reference for .NET Framework, .NET Core and .NET 5+
Linux license used on Windows machine. Running in restricted mode. How to export and import CompleteFTP configuration between servers and versions
Logging is currently turned off. How to enable Debug logging in CompleteFTP for troubleshooting
Logging level set to DEBUG How to enable Debug logging in CompleteFTP for troubleshooting
login attempts over a period of IP filtering and whitelisting in CompleteFTP: what it supports and how to configure it
matches neither control channel IP Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
Maximum site connections exceeded CompleteFTP: System.OutOfMemoryException during SFTP, or a service that stops responding
MODP groups below 2048 bits must not be used. How to disable weak ciphers and encryption algorithms in CompleteFTP
must have at least one algorithm enabled. How to disable weak ciphers and encryption algorithms in CompleteFTP
NET::ERR_CERT_COMMON_NAME_INVALID Why an SSL certificate won't import into CompleteFTP, and how to fix it
No acceptable DH group size: How to disable weak ciphers and encryption algorithms in CompleteFTP
No available ports in the range Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
No interfaces bound. Port CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
No LDAP configuration found Using Active Directory, Entra ID (Azure AD), SAML and LDAP groups to control who can log in to CompleteFTP
No supported authentication methods available (server sent: ) SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
No supported authentication methods available (server sent: publickey) SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
not allowed by filter: IP filtering and whitelisting in CompleteFTP: what it supports and how to configure it
OnConnected failed: Exception of type 'System.OutOfMemoryException' was thrown. CompleteFTP: System.OutOfMemoryException during SFTP, or a service that stops responding
Only certificates with RSA keys are currently supported. Why an SSL certificate won't import into CompleteFTP, and how to fix it
Opening BINARY mode data connection for listing Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
Partial success - also require publickey SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
PASV external IP address set but not used as configured for FTPS only Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
PASV external IP address setting is invalid: Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
PASV port range [0,0] Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
Permission denied (publickey). SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
Please ensure a private key has been supplied and that the correct password has been used Why an SSL certificate won't import into CompleteFTP, and how to fix it
Please select a file with one of the following extensions: cer, pem, pfx, p12. Why an SSL certificate won't import into CompleteFTP, and how to fix it
read file failed Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it
CompleteFTP: System.OutOfMemoryException during SFTP, or a service that stops responding
Receive error: Exception of type 'System.OutOfMemoryException' was thrown. CompleteFTP: System.OutOfMemoryException during SFTP, or a service that stops responding
Remote window size decreased to 0 Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it
Remote window size decreased to 1 Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it
remote window: waitForWindowSpace called when stopped Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it
remote window: waitForWindowSpace timed out Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it
Removed authentication method 'password' SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
Running .NET standard version Does edtFTPnet/PRO support .NET 8? Which assembly to reference for .NET Framework, .NET Core and .NET 5+
Running .NET version Does edtFTPnet/PRO support .NET 8? Which assembly to reference for .NET Framework, .NET Core and .NET 5+
send failed: socket closed CompleteFTP: System.OutOfMemoryException during SFTP, or a service that stops responding
Sending SSH_FXP_STATUS Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it
Sent SSH_MSG_USERAUTH_FAILURE: no more auth methods available SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
Server certificate does not have a private key! Why an SSL certificate won't import into CompleteFTP, and how to fix it
server error: check server log at CompleteFTP: System.OutOfMemoryException during SFTP, or a service that stops responding
Server refused our key SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
Server refused public-key signature despite accepting key! SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
Server sent passive reply with unroutable address Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
Service cannot be started. CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
SSH Server CBC Mode Ciphers Enabled How to disable weak ciphers and encryption algorithms in CompleteFTP
SSH Supports Weak Cipher How to disable weak ciphers and encryption algorithms in CompleteFTP
SSH Supports Weak MAC How to disable weak ciphers and encryption algorithms in CompleteFTP
SSH Weak MAC Algorithms Enabled How to disable weak ciphers and encryption algorithms in CompleteFTP
SSL Medium Strength Cipher Suites Supported (SWEET32) How to disable weak ciphers and encryption algorithms in CompleteFTP
Strong name validation failed. Does edtFTPnet/PRO support .NET 8? Which assembly to reference for .NET Framework, .NET Core and .NET 5+
System.DirectoryServices.DirectoryServicesCOMException: An operations error occurred. Using Active Directory, Entra ID (Azure AD), SAML and LDAP groups to control who can log in to CompleteFTP
System.OutOfMemoryException: Exception of type 'System.OutOfMemoryException' was thrown. CompleteFTP: System.OutOfMemoryException during SFTP, or a service that stops responding
System.Runtime.InteropServices.COMException: The server is not operational. Using Active Directory, Entra ID (Azure AD), SAML and LDAP groups to control who can log in to CompleteFTP
The certificate cannot be set to a null reference when creating a server socket. Why an SSL certificate won't import into CompleteFTP, and how to fix it
The certificate key algorithm is not supported. Why an SSL certificate won't import into CompleteFTP, and how to fix it
The client instructed the server to await an incoming passive data connection, but it never arrived Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
The Complete FTP Server service failed to start due to the following error: CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
The CompleteFTP service is not currently running on this machine. CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
The negotiation of encryption algorithm has failed How to disable weak ciphers and encryption algorithms in CompleteFTP
The negotiation of host key verification algorithm has failed How to disable weak ciphers and encryption algorithms in CompleteFTP
The negotiation of key exchange method has failed How to disable weak ciphers and encryption algorithms in CompleteFTP
The negotiation of MAC algorithm has failed How to disable weak ciphers and encryption algorithms in CompleteFTP
The public key of the certificate does not match the value specified. Why an SSL certificate won't import into CompleteFTP, and how to fix it
The service did not respond to the start or control request in a timely fashion. CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
The system cannot find the file specified CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
The versions of the client CompleteFTP service fails to start after an upgrade: how to find the cause and fix it
This trial assembly cannot be used with a production license Does edtFTPnet/PRO support .NET 8? Which assembly to reference for .NET Framework, .NET Core and .NET 5+
Timed out waiting for RETR/STOR/LIST/APPE command Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
TLS ciphers using Cipher Block Chaining (CBC) mode are enabled How to disable weak ciphers and encryption algorithms in CompleteFTP
TLS Service Supports Weak Cipher Suite How to disable weak ciphers and encryption algorithms in CompleteFTP
Too many connections to this site CompleteFTP: System.OutOfMemoryException during SFTP, or a service that stops responding
Unable to cast object of type 'AsymmetricCipherKeyPair' to type 'RsaPrivateCrtKeyParameters' Why an SSL certificate won't import into CompleteFTP, and how to fix it
Unhandled exception in server CompleteFTP: System.OutOfMemoryException during SFTP, or a service that stops responding
Unknown private key format: Why an SSL certificate won't import into CompleteFTP, and how to fix it
Unknown public key algorithm rsa-sha2-512 SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
Unsupported public key algorithm SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
UntrustedRoot - A certification chain processed correctly but terminated in a root certificate not trusted by the trust provider. Why an SSL certificate won't import into CompleteFTP, and how to fix it
Upgrading to version: How to export and import CompleteFTP configuration between servers and versions
User attempted AUTH but no certificate available Why an SSL certificate won't import into CompleteFTP, and how to fix it
WaitForWindowSpace timed out Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it
Weak Host Key Algorithm(s) (SSH) How to disable weak ciphers and encryption algorithms in CompleteFTP
Windows Interactive logon succeeded for Using Active Directory, Entra ID (Azure AD), SAML and LDAP groups to control who can log in to CompleteFTP
Windows license used on Linux machine. Running in restricted mode. How to export and import CompleteFTP configuration between servers and versions
without PASV sent - disconnecting Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out
Wrong key supplied for this user SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)"
Wrong type returned from ReadObject(): Why an SSL certificate won't import into CompleteFTP, and how to fix it

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