CDB error message prevents debugging

The following message prevents me from debugging an application with a self-built 4.3:

Internal error: The extension C:\dev\qtcreator-qt5-dev-d\lib\qtcreatorcdbext64\qtcreatorcdbext.dll cannot be found.

If you have updated Qt Creator via Maintenance Tool you may need to rerun the Tool and select "Add or remove components"and then select the

Qt > Tools > Qt Creator > Qt Creator CDB Debugger Support component.

If you build Qt Creator from sources and want to use a cdb executablewith another bitness than your Qt Creator build,

you will need to build a separate cdbextension with the same bitness as the cdb you want to use.

If I check the ABI for the Qt 5 dev build that I built Creator with, it says:

x86-windows-msvc2015-pe-64bit

The only CDB I have specified for Creator is 64 bit:

C:\dev\Windows Kits\10\Debuggers\x64\cdb.exe

Also note the missing spaces in the message.