libQtWebKit.so.4: cannot open shared object file

[Qt Coder]

I was using Qt 4.4.3 ,on linux but now I have downloaded and installed Qt 4.6.2 on Linux to access web.

when I run code

QWebView *view = new QWebView(parent);
        view->load(QUrl("http://85.199.39.240/view/view.shtml"));
        view->show();

QWebView *view = new QWebView(parent);
        view->load(QUrl("http://85.199.39.240/view/view.shtml"));
        view->show();

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it compiles without error but when I run exe it gives error

error while loading shared libraries: libQtWebKit.so.4: cannot open shared object file: No such file or directory

error while loading shared libraries: libQtWebKit.so.4: cannot open shared object file: No such file or directory

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I included

QT  +=  webkit

QT  +=  webkit

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in my .pro file ,also I included

#include <QtWebKit>

#include <QtWebKit>

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in my cpp file .

why this error occures?

[squidge]

Perhaps you don't have the libQtWebKit version 4 installed in any directory specified by library (LD) path?