Hi Uwe,
thank you for your response. I really appreciate it. In my first try to install qwt I did not change the qwtconfig.pri. So the configuration was debug_and_release.
I fully understand the problems with DEBUG & RELEASE builds.
Again, the error under "Tools->Form Editor->About Qt designer plugins..." was the following with the "debug_and_release" configuration:
"Cannot load library C:/Qwt-6.1.0-rc3/plugins/designer/qwt_designer_plugin.dll: Die angegebene Prozedur wurde nicht gefunden"
Am I missing something in qt.conf? It seems that the designer plugin is not able to find another required DLL or lib.
Here is my qt.conf again:
[Paths]
Libraries=../lib/qtcreator
Plugins=C:/Qwt-6.1.0-rc3/plugins
Headers=C:/Qwt-6.1.0-rc3/include
Documentation=C:/Qwt-6.1.0-rc3/doc
Libraries=C:/Qwt-6.1.0-rc3/lib
Thanks in advance!
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