Comment 3 for bug 1017798

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You might want to read https://forums.virtualbox.org/viewtopic.php?f=7&t=44576

I had the same problem, and was able to solve it (see my posting dated 2 Sept 2012).

To the developers:
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I think the issue is that updates are not done properly when we use the usual/standard tools. Installing the new package should not require to remove the old one, or should remove it automatically.
Likewise, any new version should either be able to work with the old configuration files, or should be able to remove them and replace them by new ones.