facing problem with Web Edition

I think you downloaded the trial for the full version, not the web version. When I started the web edition it offered to install a license file for the full version or run the software as the web edition. You will either need to uninstall it and then download the web edition, or buy a license for the full version.

i think there is problem of keys stored in registry. i was installed first trial software and after web edition. so this problem because of this process.

If that's the case you can probably get rid of it by uninstalling all altera tools, and then reinstalling the web edition. If that doesn't work, try deleting the altera directory, and then emptying the trash. After that delete anything with altera in it in the registry with regedit (or something similar).

yes now i format PC and installed it again. now it is running without error.

A bit drastic :) but that will work too.

but after installed and for 1st run it gives following message.

sorry, but that screen shot is way too small to read. Just cut & paste the text next time.