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Troubleshooting Thunderbird Email Client Quirks

written by: Profacgillies•edited by: Jean Scheid•updated: 7/6/2011

Thunderbird is my email client of choice and I have always been happy with it. The trouble is, that Thunderbird has some strange quirks, leading to some strange error messages,which if you don’t know about them can drive you mad trying to overcome.

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    Let me nail my colours to the mast at the start. I use Thunderbird as my Email client. It runs across my home wireless network and generally I don’t notice it, which is what I want from an Email client. There are good reviews elsewhere in Brighthub outlining the merits of Thunderbird, so I won’t bother to repeat its virtues.

    The problem is that in spite of its undoubted virtues, Thunderbird does have some quirks. Here are a couple of error messages I have seen more than once:

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    "Thunderbird is already running, but not responding. To open a new window you must close the existing thunderbird process, or restart your system"

    This error is a little off putting. When it came up on my screen, I did not have a copy of Thunderbird running. I went to task manager and checked that there was no Thunderbird process running in the background.

    The answer is that the error message is not strictly accurate. The error is usually caused by the presence of a file called parent.lock which locks up the system. The solution lies in deleting this file. It can be found in the profile folder for Thunderbird. This will be inside Program Files\Mozilla Thunderbird if you’ve not moved things around. (like I had!). Some forum responses also suggest that the offending file may be in the corresponding location for Firefox and that this can interfere, but I have not experienced this form of the error. I can reassure you that when I deleted the offending file, the application loaded fine and no side effects were experienced.

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    "Error opening file for writing: r\n\r\nmozMapi32.dll\r\n\r\nClick Retry to try again, or\r\nCancel to stop the installation."

    This one had me really puzzled. Apart from anything, it appeared to be written in the kind of fluent Hungarian that is favoured by people more technically minded than myself.

    It appeared as Thunderbird was trying to automatically upgrade itself. It places the computer in an annoying loop. If you select retry the message re-appears, if you cancel, then you simply repeat the problem at a later date.

    It turns out that the usual cause of this error is having a Logitech webcam installed on your system. If you install the Quickcam software and already have Thunderbird installed, it will set Thunderbird as its default associated email client. If Thunderbird is set as your default email program in the Quickcam software, Quickcam will not let Mozilla update the file.

    The fix is to disable the webcam by right-clicking the Quickcam icon in the system tray and selecting "Exit") and try again. Once the upgrade is complete, Quickcam can be restored, although the problem seems to be associated with each incremental upgrade of Thunderbird v2, so be prepared to disable Quickcam again.

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    Conclusion: Why am I still using Thunderbird?

    I stated at the outset that I am still a Thunderbird user. This is because its undoubted merits as an Email client. It is also because of its open source nature. With an open source application as widely deployed as Thunderbird, you can rest assured that even the most obscure error message can be cut and pasted into Google and a solution will emerge. This is how I found the solutions presented here. The same cannot always be said of commercial applications. After all, the second quirk seems to me to be a problem with the Logitech software, not with Thunderbird.

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    Value for money

    Rating Average

    It's free! and generally it works well.

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    Rating Average

    Thunderbird is a flexible and user-friendly emial client with a good range of add-ons

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    Helpfulness of error messages

    Rating Average

    Thunderbird generates a range of fairly unhelpful error messages

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    Usefulness of web forums to solve problems

    Rating Average

    There are a wide range of web forums with lots of useful information to solve problems