I tried changing the path to the Qt directory but its still not helping

Let me explain the problem once agian -
When I open the assistant from Qt Demo, it works fine for the text browser area. But when I click on some item from the index list, I get the error as 'D:/4.2.2/....' not found. D:/4.2.2 was previous directory where I had installed Qt. Then I installed Qt again to D:/Qt/4.2.2 . I didnt uninstall the previous one, just deleted the directory(I dont know how to uninstall Qt )
In short Text browser works fine... but the clicks on index list doesn't work ...

I guess thers something in the registry for this problem.
ne suggestions ??