CompleteFTP Knowledge Base
Each article covers a single problem, is written against a specific CompleteFTP release, and records what was verified and when.
These are the problem-first companions to the product guide. If you are setting something up for the first time, start with the guide. If something is already broken, start here.
Troubleshooting
Something is failing and you need to know why.
- CompleteFTP service fails to start after an upgrade: how to find the cause and fix it I upgraded CompleteFTP and now the service will not start · the service starts and then stops immediately Windows · verified 3 August 2026
- CompleteFTP: System.OutOfMemoryException during SFTP, or a service that stops responding CompleteFTP service becomes unresponsive and drops connections · System.OutOfMemoryException in the CompleteFTP log Windows, Linux · verified 3 August 2026
- Passive FTP and FTPS data connection failures in CompleteFTP: login works, the directory listing times out I can log in over FTP but the directory listing never appears · FileZilla connects and authenticates, then times out on LIST Windows, Linux · verified 3 August 2026
- SFTP login fails with "No supported authentication methods available (server sent: publickey)" or "Permission denied (publickey)" no supported authentication methods available (server sent: publickey) · why does the server only offer publickey when I set password authentication? Windows, Linux · verified 30 July 2026
- Why SFTP transfers fail with "ConsumeWindowSpace timed out", and how to fix it SFTP transfer of a large file fails partway through · ConsumeWindowSpace timed out on files over 1GB Windows, Linux · verified 30 July 2026
- Why an SSL certificate won't import into CompleteFTP, and how to fix it I cannot import my SSL certificate into CompleteFTP · it says the private key is wrong or the password is incorrect but both are correct Windows, Linux · verified 30 July 2026
How-to
A procedure, with the traps that are not in the guide.
- How to disable weak ciphers and encryption algorithms in CompleteFTP a vulnerability scan flagged weak ciphers on our CompleteFTP server · how do I disable CBC ciphers in CompleteFTP? Windows, Linux · verified 30 July 2026
- How to enable Debug logging in CompleteFTP for troubleshooting how do I enable logging at the debug level? · where can I find Diagnostics.log? Windows, Linux · verified 30 July 2026
- How to export and import CompleteFTP configuration between servers and versions I see a configuration import prompt during install but no export ability · can I export the config from one CompleteFTP server and import it into another Windows, Linux · verified 3 August 2026
- Using Active Directory, Entra ID (Azure AD), SAML and LDAP groups to control who can log in to CompleteFTP we are unable to link FTP with a group from AD · can I add an Active Directory security group as a user in CompleteFTP? Windows, Linux · verified 3 August 2026
Administration
What the product does and does not support.
- IP filtering and whitelisting in CompleteFTP: what it supports and how to configure it does CompleteFTP support IP whitelisting and blacklisting? · how do I block or ban a specific IP address? Windows, Linux · verified 30 July 2026
Explainers
How a mechanism actually behaves.
- Does edtFTPnet/PRO support .NET 8? Which assembly to reference for .NET Framework, .NET Core and .NET 5+ does edtFTPnet/PRO support .NET 8 · is there a version of edtFTPnetPRO that supports .NET 6 and above Windows, Linux, macOS · verified 3 August 2026
Looking up an error?
Every error message these articles cover is listed verbatim on one page, so you can search for the text in front of you.
Error message indexSetting up?
These articles are for when something is wrong. To configure CompleteFTP from scratch, start with the product guide.
CompleteFTP guide