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I can't open Thunderbird anymore on my MacBook and get the message "You can't open the application because it may be damaged or incomplete"

  • 8 replies
  • 2 have this problem
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  • Last reply by se310

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Hello, Thunderbird doesn't open anymore on my MacBook pro (OS X Yosemite 10.10.5) since yesterday. It still appears on the dock and in the applications folder but not with the right icon - there is a generic icon instead. When I try to open it, the message "You can't open the application Thunderbird because it may be damaged or incomplete". Something puzzling is that I can't see the folder Thunderbird in the Library folder either. Does it mean I lost emails that were stored locally as well as my profile? I ran disk utility which prompted to disk repair since it found something wrong in the catalogue (I don't know whether that was related to Thunderbird). But the problem with Thunderbird was still there after the repair and the reboot... Thanks for your help and advice. Stephane

Hello, Thunderbird doesn't open anymore on my MacBook pro (OS X Yosemite 10.10.5) since yesterday. It still appears on the dock and in the applications folder but not with the right icon - there is a generic icon instead. When I try to open it, the message "You can't open the application Thunderbird because it may be damaged or incomplete". Something puzzling is that I can't see the folder Thunderbird in the Library folder either. Does it mean I lost emails that were stored locally as well as my profile? I ran disk utility which prompted to disk repair since it found something wrong in the catalogue (I don't know whether that was related to Thunderbird). But the problem with Thunderbird was still there after the repair and the reboot... Thanks for your help and advice. Stephane

Chosen solution

The profile folder location is explained here:

http://kb.mozillazine.org/Profile_folder_-_Thunderbird#Mac_OS_X

The profile folder and the folder with the program files are separate, and uninstalling or reinstalling the program doesn't affect the profile folder that contains all user data. I can't tell if your profile folder has been deleted or is located elsewhere.

Installing TB on OSX

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All Replies (8)

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This may be due to a cached files issue:

https://discussions.apple.com/thread/8421344

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Hello, Thanks. I tried this but I still have the same problem after clearing the cache files....

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There are lots of suggested fixes for this error. If the clearing of cache files doesn't help, maybe this does:

https://www.youtube.com/watch?v=3py0kgq95Hk

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Thanks, I tried this as well ... It didn't work ... Beside the fact that I can't open Thunderbird, I am worried that I don't see a thunderbird folder in my MacBook's library folder either. I am not sure if there should be one but I guess this is where the profile files are saved ... I could make a re-install of the software but I am not sure if my configuration and the emails I saved locally are saved elsewhere than in the library .... Does anyone know anything about that?

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Chosen Solution

The profile folder location is explained here:

http://kb.mozillazine.org/Profile_folder_-_Thunderbird#Mac_OS_X

The profile folder and the folder with the program files are separate, and uninstalling or reinstalling the program doesn't affect the profile folder that contains all user data. I can't tell if your profile folder has been deleted or is located elsewhere.

Installing TB on OSX

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Thanks for the explanations! I just re-downloaded and re-installed thunderbird and everything was back on as it was before. It was just probably an auto-update that went wrong ... I am still intrigued by the fact that the profile folder isn't located in the library folder of my macbook. I don't where to find it ...

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Glad to hear it's working again. You can always find the profile from Help/Troubleshooting Information, click Open (or Show) Folder, or click about:profiles.

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Interesting! by following your advice, I found out that there was a second library folder in a different location than the one I was browsing. And it is hidden, so I wouldn't be able to find it using spotlight but I could access this folder through the Thunderbird throubleshoothing information. Thanks again for your help! There was no reason to panick after all!