#52 SASL error when connecting to Gmail on macOS

[Greg Anders]

I'm getting the following error when trying to connect to Gmail on macOS 10.14.6:

Error: SASL(-7): invalid parameter supplied: Parameter Error in /BuildRoot/Library/Caches/com.apple.xbs/Sources/passwordserver_saslplugins/passwordserver_saslplugins-192.30.1/plain_clienttoken.c near line 195

I don't have any problem connecting and syncing with my other mail server.

Here is my (abridged) .mbsyncrc file.

IMAPAccount gmail
Host imap.gmail.com
User my.email@gmail.com
Pass my-password
SSLType IMAPS
CertificateFile /etc/ssl/cert.pem

IMAPStore gmail-remote
Account gmail

MaildirStore gmail-local
Subfolders Verbatim
Path ~/.mail/gmail/
Inbox ~/.mail/gmail/Inbox

Channel gmail-inbox
Master :gmail-remote:
Slave :gmail-local:
Patterns INBOX

Channel gmail-sent
Master :gmail-remote:"[Gmail]/Sent Mail"
Slave :gmail-local:Sent

Channel gmail-trash
Master :gmail-remote:"[Gmail]/Trash"
Slave :gmail-local:Trash

Channel gmail-archive
Master :gmail-remote:"[Gmail]/All Mail"
Slave :gmail-local:Archive

Group gmail
Channel gmail-inbox
Channel gmail-sent
Channel gmail-trash
Channel gmail-archive

[Oswald Buddenhagen]

please try the tip of the 1.3 branch; this might be fixed.

[Greg Anders]

Unfortunately not -- I tried both with Homebrew (using brew install --HEAD isync) and building directly from git. Same error in both cases.

[Greg Anders]

A few more data points:

$ mbsync -v
isync 1.3.1

The same config works on another Ubuntu machine I use (that one uses isync 1.3.0).

When I add the verbose -V flag, I see the following on macOS:

Authenticating with SASL mechanism PLAIN-CLIENTTOKEN...
Error: SASL(-7): invalid parameter supplied: Parameter Error in /BuildRoot/Library/Caches/com.apple.xbs/Sources/passwordserver_saslplugins/passwordserver_saslplugins-192.30.1/plain_clienttoken.c near line 195

but on Ubuntu I see

Authenticating with SASL mechanism PLAIN...

so perhaps this has something to do with this problem? If so, how can I tell macOS to use SASL PLAIN?

[Oswald Buddenhagen]

as per documentation, AuthMech PLAIN.
it would be interesting to know why it is failing with the newly found mechanism, though.

[Greg Anders]

Ah yes, sorry, I missed that somehow.

I can confirm that using AuthMechs PLAIN fixes the problem.

[Oswald Buddenhagen]

no further info forthcoming, so i'll leave it at the workaround.