Thanks for quick n valuable inputs.
I tried your inputs, but I have found that page has huge viewstate with page size 169 KB. We have developed such large pages earlier too, but such issues never occured.
I found one blog on net and tried this :http://blogsandip.wordpress.com/2008/06/06/page-cannot-be-displayed-error-on-aspnet-post-back/
I tried viewstate chunking but it didn't work, at last I made viewstate false for page, and now page started rendering. So now there is no issue like "page cannot be displayed" after postback. I am not able to get this, if there is no issue of viewstate on one machine, then how come it's on other machine. Also both machine are on same network, sharing same internet connection.