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how to ensure 100% folder synchronization?

  • 6 replies
  • 1 has this problem
  • 20 views
  • Last reply by kuzja

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I have created a new TB account for accessing my gmail using imap. I also configured the imap synchronization according to this guide: https://support.mozilla.org/en-US/kb/imap-synchronization

To ensure that all my mail was downloaded for offline use, I switched Thunderbird to offline and selected to "download messages for offline use before going offline". Then I waited until TB finished downloading and went offline. There was no error message.

However, later on I found that some folders were not fully synchronized. E.g. the "All Mail" folder was missing about two years of data.

How can I ensure that the synchronization was finished 100% and no data is missing? As the amount of mail is huge and there are many sub-folders, it is not feasible to process every folder one by one.

I have created a new TB account for accessing my gmail using imap. I also configured the imap synchronization according to this guide: https://support.mozilla.org/en-US/kb/imap-synchronization To ensure that all my mail was downloaded for offline use, I switched Thunderbird to offline and selected to "download messages for offline use before going offline". Then I waited until TB finished downloading and went offline. There was no error message. However, later on I found that some folders were not fully synchronized. E.g. the "All Mail" folder was missing about two years of data. How can I ensure that the synchronization was finished 100% and no data is missing? As the amount of mail is huge and there are many sub-folders, it is not feasible to process every folder one by one.

Modified by kuzja

All Replies (6)

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How can I ensure that the synchronization was finished 100% and no data is missing?

IMV you can't. I do use this add-on as a kind of workaround. It allows to compare the size of local folder with the size of the folder on the server. https://nic-nac-project.org/~kaosmos/index-en.html#foldersize

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christ1 said

... I do use this add-on as a kind of workaround. It allows to compare the size of local folder with the size of the folder on the server. https://nic-nac-project.org/~kaosmos/index-en.html#foldersize

It might be a workaround, but I am afraid there are several potential issues:

  • Does it work with IMAP saved mail folder ("ImapMail" folder in my TB profile)? I do not use Local Folders ("Mail/Local Folders").
  • Does it compare only the size, or the number of messages as well? With a big folder (>1GB), small messages could be lost...
  • Can I use it on the whole account, or do I have to compare folder by folder? (See my note about lots of folders in my previous post.)

Btw what could be a reason the synchronization does not finish completely, without any notice? Is it a TB bug?

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It might be a workaround, but I am afraid there are several potential issues:

I don't disagree.

Does it work with IMAP saved mail folder ("ImapMail" folder in my TB profile)?

Yes, it does.

what could be a reason the synchronization does not finish completely, without any notice? Is it a TB bug?

I don't know. In general, mail servers are not made for mass transactions, so synchronization will probably complete at some point.

You can also take a look at the Activity Manager. At the top right of the Thunderbird window, click the menu button > Activity Manager

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You can also take a look at the Activity Manager.

Well, the Activity Manager is a good hint, I was not aware of it. Of course, it does not ensure the completeness of the data transfer, but might be helpful to keep the track of what was done. Thanks.

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What I think you need to be aware of is Google will throttle your bandwidth use. Some folks report the throttling cutting in after a few a thousand emails, Google claim a very large daily allowance for data, but I think their mail server throttle what is a very intensive CPU task of uploading large quantities of mail.

You should also be aware your anti virus may impact the performance as it meddles in the data stream looking for nasties.

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Matt: I understand the problem can be on Google side (would not be surprised). Unfortunately I don't have another mail account with similar amount of data to test it.

Antivrus is not in game here, as I am using Linux.

Thanks for your suggestions.