IMAP sync with Office365 server

User Help for Mozilla Thunderbird
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Joined: September 9th, 2019, 10:08 am

Post Posted September 9th, 2019, 10:33 am

I am using TB for my work account on Office365 cloud server, with IMAP protocol, which is supported on Office server.

At this moment I have issue that when using TB there are some folders (grey/italics) which do not exist on server. I can not delete it, move it, nothing. The same situation is on my two computers. I even tried to deinstall TB and install it again, but always the same. On one computer I installed the latest version of TB (64 bit).

For example, in Trash folder on PC in TB i have tens of folders, and I can not empty the trash folder. I tried to make log files, and those folders do not have flag /Noselect).

Does anyone had similar situation, and have any idea how to solve this. I really do not want to use Outlook on premise on my PC.


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Joined: February 12th, 2005, 8:33 pm

Post Posted September 13th, 2019, 12:05 pm

I don't know if it is the case with Outlook or Office 365, but I had a similar problem with a standard server.
The problem is usually synchronisation. I think the grey folders are folders that are synchronized for whatever reason in Thunderbird but don't exist anymore on the server (ex.: you deleted them via the web interface or another webmail client). Thunderbird usually removes the "sync" flag of these unexisting folders, but sometimes it doesn't remove the flag and tries to access these phantom folders that don't exist anymore on the server.

Things to check.

1. To make sure, close Thunderbird and open the web interface. Make sure these folders don't exist on the server.
Close the web interface.

2. Start Thunderbird.
Right-click on the account name and select on "Synchronisation and disk space" (my TB is in French so names may vary).

3. Click on Advanced.
Look at the list of synchronized folders for that account and make sure you don't have any folders listed there that are synchronized (checked) but that you didn't see on the web interface. Check especially the folders that appeared in grey in TB.
Uncheck them.

4. Quit Thunderbird and restart.
If the problem is as described, these grey folders will have disappeared.

UPDATE. The problem also happens with Gmail if you change the language of the web interface.
Michel Gagnon
Montréal (Québec, Canada)


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Post Posted September 13th, 2019, 4:32 pm

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