Incompatible library version: libQtGui.4.dylib requires version 45.0.0 or later, but libpng12.0.dylib provides version 44.0.0

[thomas.haymore@…]

Installed PySide through macports with dependencies, but when import module in python, get following error:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: dlopen(/opt/local/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/PySide/QtGui.so, 2): Library not loaded: /opt/local/lib/libpng12.0.dylib
  Referenced from: /opt/local/lib/libQtGui.4.dylib
  Reason: Incompatible library version: libQtGui.4.dylib requires version 45.0.0 or later, but libpng12.0.dylib provides version 44.0.0

I have already tried:

sudo port selfupdate
sudo port upgrade outdated

and

sudo port -n upgrade --force libpng

All with no effect. I'm using a Mac 10.6.

[ryandesign (Ryan Carsten Schmidt)]

libpng was upgraded to 1.4 a long time ago. See #29831 for some steps you can try.

[thomas.haymore@…]

Here's what ended up happening (in addition to steps above):

1. When I tried to uninstall libpng, I discovered I had two versions installed, 1.2 and 1.4.
2. I tried uninstalling only 1.2 and forcing 1.4 to upgrade, but that didn't work
3. Uninstalled everything, libpng, qt4, and py26-pyside
4. reinstalled qt4 and py26-pyside and dependents
5. everything seems to work fine now

Thanks for the help.

[ryandesign (Ryan Carsten Schmidt)]

Ok, glad you got it working.