After reinstalling Python (3.4) as well as OSGeo4W and the QGIS Standalone, my QGIS always crashed when "Starting Python" on my Windows 7 64 Bit environment. It simply did not proceed to the QGIS-GUI to be of any use. Furthermore, this happened on the way:
As I was beginning to write a plugin for QGIS, I faced a problem where the ui-compiler for qt-uis wouldn't work without telling it where the PYTHONHOME and PYTHONPATH is. As advised in a post here on gis.stackexchange, I set the respective system variables and added PYTHONHOME to my PATH-variable as well. The two steps ui-compilation worked, the test-plugin was finally ready but... QGIS refused to start as mentioned.
No errors are thrown/logged.
How do I get Quantum GIS 2.4 Chugiak back to work?