Folder creation fails sporadically with "Mailbox already exists."

[m3nu]

On first sync, I need to run offlineimap in a loop due to these errors in folder creation. Some kind of race condition?

Folder 'INBOX/20 Karajangasse/K&AOQ-ufer/T11 - Gabler'[***_exchange] could not be created. Server responded: ('NO', ['Mailbox already exists.'])

[nicolas33]

Do you have nametrans rules? Also check http://offlineimap.org/doc/FAQ.html#i-get-a-mailbox-already-exists-error.

[maugsburger]

I get a similar bug, syncing to an Exchange 2013 server:
Creating folder INBOX/01 Todo/Trash[info-exc] Creating folder INBOX/01 Todo[info-exc] ERROR: Creating folder INBOX/01 Todo on repository info-exc

Probably, it's because Exchange automatically creates the INBOX/01 Todo when INBOX/01 Todo/Trash is created - but offlineimap doesn't mark it as created, because it's a parent-folder-less subfolders (as e.g. dovecot supports it).

[nicolas33]

Does this error happen again on next sync?

BTW, I think offlineimap should create folders in order of the hierarchy to avoid such issue.

[maugsburger]

No, it doesn't happen again on the next sync. I needed to run offlineimap several times until all folders were created successfully, then everything works smoothly.