Ssl error with offlineimap version 6.6.1 (debian package)

Nicolas Sebrecht nicolas.s-dev at
Sat Feb 6 18:54:10 GMT 2016

On Sat, Feb 06, 2016 at 05:40:42PM +0100, Leandro Noferini wrote:

> My imap server is courier with an selfsigned certificate and it worked
> fine for many years but some days ago it began to give me this error:
> leandro at tricheco:~$ offlineimap -a BBs


> ERROR: Unknown SSL protocol connecting to host '' for repository 'RemotoBBs'. OpenSSL responded:
> [SSL: SSL_NEGATIVE_LENGTH] dh key too small (_ssl.c:590)


> What could be the error?

SSL defaults have change. Check your configuration, especialy
ssl_version and tls_level:

OfflineIMAP must be configured to enable a protocol that the server

Also, you might like to check the output of --info.

Nicolas Sebrecht

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