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Oulook/Hotmail Calendar remains ReadOnly

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  • Last reply by sfhowes

Lothar Zeitler
Lothar Zeitler
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Hi all, I am new with TB. I added on my Linux box two accounts. One is the Outlook (Microsoft Account) Email, the other Gmail. Email works perfectly well. I learned that TB need a seperate calendar configuration. First, I added both, Google and OL and both calendars were Readonly. I found an Add-On for Google Calendar, which remediated the issue and I can use the calendar. But I have not found anything with can help with outlook/hotmail calendar. Another Client BlueMail works with both. I want to stay with Thunderbird and I am wondering if someone can share some tipps and / guidance. This would be fantastic.

The Errormessage is: An error occured when writing to the calendar Hotmail. Please see below for more information. Error code: MODIFICATION_FAILED

Hi all, I am new with TB. I added on my Linux box two accounts. One is the Outlook (Microsoft Account) Email, the other Gmail. Email works perfectly well. I learned that TB need a seperate calendar configuration. First, I added both, Google and OL and both calendars were Readonly. I found an Add-On for Google Calendar, which remediated the issue and I can use the calendar. But I have not found anything with can help with outlook/hotmail calendar. Another Client BlueMail works with both. I want to stay with Thunderbird and I am wondering if someone can share some tipps and / guidance. This would be fantastic. The Errormessage is: An error occured when writing to the calendar Hotmail. Please see below for more information. Error code: MODIFICATION_FAILED

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sfhowes
sfhowes
  • Top 10 Contributor
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I added my Hotmail calendar (as an MS Office 365 type) with the TbSync/Provider for Exchange ActiveSync add-ons. If you right-click the calendar in the Calendar Pane, Properties, there is a checkbox for Read only (see picture).

Google calendars can be added with the built-in CalDAV option:

https://support.mozilla.org/en-US/kb/using-lightning-google-calendar