First of all i thank Baxter and paul.
Paul,
I re-installed designer and notes client and as a miracle, it works now. I didn't do anything new. But now i can preview.
But i need to know what is behind this thing for the next time if the same problem arises, i don't know what to do.
What are all needed to be learnt for this?
The next step is to develop applications. Need help for that too..!!
If ok for you, we could share our contacts so that we can make our communication faster. My mail is: vijayaragavank@kkmsoft.com.
Thanks...