Yes, find a thread where there are answers to this question, but it will be hard ... most of the threads are finished with post link mine.
If you find the answer, please write a faq entry in the wiki, so next time I can post a link, to it...
Try this steps:
1. test the compiler from the command line
2. if it works, goto settings -> compiler & debugger -> compiler -> toolchain
3. verify that the path is correct (I think you've to remove "bin", from it) and that all executables are spelled correctly.
p.s. cross posting is forbidden, too
p.p.s.
However, the MinGW64/bin directory has been added to the "%path%" (twice!), once by the installer and once by me.
In an attempt to resolve this issue, I have change the toolchain in the "Settings->Compiler/Debugger->Toolchain Executables" from the default "gcc" to "x86_64-w64-mingw32-gcc.exe". I did the same with the g++'s entries. But this did not change anything.
If I remember correctly, C::B is not using the %path% variable!