I'm just guessing here, but as the exception suggests it means that there is a file you are trying to access that does not exist.

My best guesstimate (unless there is another place in the code where you are trying to access a file) is that the code wbrShow.Navigate(...) is generating that error. I'd print out the result from this - (Link & Mofaser & "/" & iSouraNo.ToString("000") & iAyaNo.ToString("000") & ".html") - in a message box and check that it is a valid link....

EDIT: I guess you should also check that any files that you are accessing are in the Release directory as well as the debug directory...