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  • Today I wanted to migrate a Gsuite email box to Cloudron. The box contained about 12GB/45k mails in about 50 folders.

    The naming convention of the folders were like:

    01. "main"
    01.01. "sub 1" (not nested)
    01.02. "sub 2" (not nested)

    In an email client I tried to move such a folder from current box to new box. This went awfully wrong!

    I checked Roundcube what was/wasn't created in Cloudron:

    folder named 01
    ... nested folder named: 01
    ... ... nested folder named: "sub 1" (Nested)

    In the first 2 folders you're not able to store mails, only in the "last" one and the emails didn't got moved (actually they disappeared).

    When creating such a folder in Roundcube you get an error that a . "dot" is not allowed.

    Isn't it very strange that you're not able to use dots in a folder name and that it creates subfolders based on those dots when created in a client?

    The only workaround was to rename in Gsuite all the 50 folders and then folder by folder move everything and double double check if everything moved correctly.

    Kind regards,


  • App Dev

    @imc67 IMAP is funky with special characters in folder names, especially with Outlook. Avoid using !@#$%^&*(){}[]:;"'<>?/|\ Periods are gonna be hit or miss, so avoid those as well. Instead, dashes and Underscores should work:

    etc etc

    I'd like to point out that this is an issue with IMAP and not cloudron.

  • @murgero aha, then Gsuite/Gmail is able to do this, will take note of this.

  • App Dev

    @imc67 gsuite / gmail is not IMAP, just to note. They support an IMAP-compatible system for syncing to Outlook and other mail clients, but gmail itself is not IMAP.

  • Staff

    Gmail import is a complicated topic and as @murgero said gmail has a IMAP compat layer but it's internal storage is not IMAP.

    See for detailed overview of importing. Also, I am not on expert on this topic since this is a bit outside the scope of Cloudron.

  • Staff

    BTW, for the "dot" thing, the mailbox separator in Cloudron is ".". This is why folders with dot don't work. If you create a folder named "", it is like subfolder bar under foo and subfolder baz under bar.

    While using "." as a seperator is not a bug as such, using "/" as a separator instead of "." would have been a better choice for Cloudron but we didn't know this when we started (sadly, "." is the dovecot default too). And also using "/" as separator is required for mailbox sharing to work. We are slowly working towards moving the separator to be "/", step by step.