解决办法:
- Run regedit.
- Hop to HKEY_CURRENT_USERSoftwareTrolltechVersions或HKEY_CURRENT_USERSoftwareDigiaVersions
- Add a new key named "bin文件夹的上一级目录" or whatever version you have.
- Under the new key, create a new string "InstallDir" valued with "C:Qt4.3-msvc2005--bin文件夹的目录":
- Run Visual Studio
- Click Qt -> Qt Options.
- The new version should be there.