QueryString security problem

Hi there.

I am working on an asp.net 3.5 web app in which there is an extensive use of QueryString values in most of the pages. This is, of course, a security problem.

In order to fix it I could convert the whole app so that it works with session values, but that would take too much time (and besides, it is not a good practice to put too much load on the session).

Another solution is to lock/hide the address bar for all of the pages.

How I can lock/hide the address bar for all the pages in the application ? Is this a wise solution to the problem ? If not, please tell me what is ...

Thanks in advance.
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