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I've just started playing with QGIS with a view to eventually developing a few simple plugins in Python. I downloaded QGIS 1.7.1 for Windows and started working through these workshop notes.

If I've understood correctly, developing plugins often uses QT Designer and something called pyuic4. These don't seem to be included in the QGIS install, so I downloaded PyQT4 separately. This enabled me to finish working through the workshop, but now when I start QGIS I get the following error:

Traceback (most recent call last):
  File "", line 1, in 
RuntimeError: the PyQt4.QtCore module is version 1 but the qgis.core
module requires version -1

If I uninstall PyQT4, the problem goes away, but then I don't have QT Designer or pyuic4, so how do I develop plugins? I'm not sure what version -1 of PyQT4 is.

Does anyone have any suggestions, please? I'm obviously doing something daft, but I'm not sure what. Perhaps QT Designer is actually included somewhere with QGIS 1.7.1, but if so I can't find it...


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up vote 2 down vote accepted

Did you install the OSGeo4W version of QGIS? If you did, you'll have pyuic4 available through OSGeo Command line.

I'm not using QT Designer but QT Creator on Win 7 (has to be installed separately), maybe that makes a difference.

share|improve this answer
Great - that works! Thanks @underdark. – JamesS Nov 7 '11 at 16:16

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