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Since yesterday I'm unable to start QtCreator. Trying to start QtCreator from terminal gives me this error message, which I haven't found anything on:

qtcreator: symbol lookup error: /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/ undefined symbol: _ZN15QPlatformWindow17formatWindowTitleERK7QStringS2_

Any ideas what this is about?

Running Ubuntu 13.04 with qt5-edgers ppa for both Ubuntu SDK and Qt.

Version of QtCreator: 2.7.0-0ubuntu4~raring1~test5

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Did you change the LD_LIBRARY_PATH variable in your .bashrc file? – hakermania May 13 '13 at 12:08
I've not done that recently, no. What should it be set to? – Daniel Holm May 13 '13 at 12:46
Searching a bit in google revealed that you may have installed 2 versions of Qt in a single system. I am not sure, though. – hakermania May 13 '13 at 12:49
Like Qt4 and Qt5? – Daniel Holm May 13 '13 at 13:06
Thanks hakermania, I removed all Qt4 stuff and it works now. – Daniel Holm May 13 '13 at 13:13

The problem happens rarely but is related to upgrading from for example the archive version of ubuntu-sdk, or maybe some more complex upgrade path. The root problem is currently unknown, but removing and reinstalling Qt 5 seems to work.

  1. Remove libqt5core5 package, to remove most of the Qt 5
  2. Install ubuntu-sdk package to get the Qt 5 and the rest of the Ubuntu SDK back.
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Thanks, this is clearer and solves the problem ^_^ – Inoe Jun 16 '13 at 11:10
up vote 2 down vote accepted

Somehow it seemed like I had two Qt versions installed (thanks hakermania). After I've removed all Qt4 stuff and reinstalled Ubuntu SDK and QtCreator (again) it worked.

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You are welcome, make sure to accept your answer when you can. – hakermania May 13 '13 at 13:14
Will do. Thanks again. – Daniel Holm May 13 '13 at 13:59

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