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How do I fix the "modification failed" error?

  • 6 replies
  • 9 have this problem
  • 1 view
  • Last reply by Matt

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When I try to add a new event to my Lightning calendar I get this error, the calendar is locked as "read only" and when I restart the app the event is no longer in the calendar. I have seen this sort of error for as long as I have been using T-bird but it has never been so total.

I am running under windows 8, T-bird ver 24.4.0 and Lightning 2.6.4. It appears I have enabled test pilot for Tbird and it is ver 1.3.9.

These calendars were copied from my old computer's hard drive and I am guessing there is something different about the format??? That Tbird was stuck on an older revision which I don't know the number.

When I try to add a new event to my Lightning calendar I get this error, the calendar is locked as "read only" and when I restart the app the event is no longer in the calendar. I have seen this sort of error for as long as I have been using T-bird but it has never been so total. I am running under windows 8, T-bird ver 24.4.0 and Lightning 2.6.4. It appears I have enabled test pilot for Tbird and it is ver 1.3.9. These calendars were copied from my old computer's hard drive and I am guessing there is something different about the format??? That Tbird was stuck on an older revision which I don't know the number.

All Replies (6)

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Right-click the calendar - Properties
Uncheck 'Read Only'

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Yes, I can figure out to uncheck the read only option. That doesn't fix the problem. Every time I try to create a new event I have the same problem where I get the error and the event is not saved.

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Did the move involve copying to a CD or DVD? Often the files on the hard disk are set to read only so any update just does not work.

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Hi, I'm not sure I understand. No, the old hard drive was put in a drive case and used to copy the data directly. I believe you are suggesting the files might be read-only which the program can't undo? Where do I look to see if the calender files are write protected?

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Is there a way to wholesale copy the data from one calendar to another? Then I could just copy the data into a new calendar, delete the old one and rename the new calendar. Would that work?

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Right click the calendar and select export as ICS.

Then try importing and see if it helps.

Are the "events" showing as your the owner... There were issues at one point where calendar items that were not "owned" by you were not able to be edited.

Help menu )Alt+H) ? troubleshooting information. Click the show button for the profile. Close Thunderbird Open the folder "Calendar data" look at the properties for all the files and make sure they are not read only. Correct as necessary.