Import of calendar fails when target is a TbSync calendar

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Joined: August 5th, 2008, 11:48 am

Post Posted October 6th, 2019, 1:57 pm

Trying to set up the add-ons "TbSync" and "Provider for CalDAV & CardDAV" to synchronize calendar & address book. Using instructions provided in article found at Purpose is to initialize a new remote calendar with data from my existing local calendar. This resulted in an error code of "MODIFICATION FAILED" with a detailed description as follows:

If you're seeing this message after snoozing or dismissing a reminder and this is for a calendar you do not want to add or edit events for, you can mark this calendar as read-only to avoid such experience in future. To do so, get to the calendar properties by right-clicking on this calendar in the list in the calendar or task view.

My experience has nothing to do with snoozing or dismissing reminders. I'm trying to load data into a new calendar as instructed in the referenced documentation. One wouldn't think that this is accomplished by making it "Read Only".

I also foresee a need to do something similar with address books. However, the TB UI does NOT seem to allow selection of an existing address book (i.e., as created by TbSync) as target for importing a previously exported file. Would be grateful if someone can explain how to do this.


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Post Posted October 6th, 2019, 10:29 pm

I installed "TbSync" and "Provider for CalDAV & CardDAV" on Thunderbird 68.1.1 under Windows 10 Home. I created a simple calendar (sticking with the default name of Home) and followed the instructions you pointed to. I configured it with fruux , telling it to just sync the calendar for now. Seems to work fine. By default I see both the local and remote calendar data in the Calendar window unless I uncheck one of the calendar names in the pane to the left.

What provider are you using? I chose fruux.

Later on I might try syncing contacts. I suspect it would be easier if I installed the CardBook add-on since its based on the CardDAV and vCard standards.

Posts: 67
Joined: August 5th, 2008, 11:48 am

Post Posted October 7th, 2019, 8:18 am

Whoops! I'm afraid I may have over reacted to the mysterious error message. When the message appeared the selected remote calendar, for TbSync, appeared empty. However, I've now noticed the check box that, I now think, controls which calendar/s is/are displayed. When I selected that, sure enough the calendar does appear to have updated. I don't know how to confirm that it is the same (i.e., contains all of the entries) as the one which was exported. However, it does contain lots of entries and could be the same from what I can see. In that, seems to be working as expected.

The meaning of the displayed error message is still a mystery but new items added to the calendar appear to be synchronized as desired. I haven't been able to find any log file that might help explain what happened to trigger the error message but maybe I needn't worry about that.

My hosting service is JustHost which I also use as an email provider. They advertise that their CalDav, CardDav support has only been tested for IOS. Possibly this is a case where IOS is conforming to open standards.

Thanks for the feedback. Sorry to have goofed.

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