Using Prism 3.00, the File..Merge command is missing.
On some computers, Prism 3 mistakenly removes the "Merge.." command from the "File" menu.
Prism 3.00 has a new command on the File menu, "Send Mail". It only works if your email program is configured in a standard way, termed MAPI. If Prism senses that your email program won't work with it, it is supposed to remove the Send Mail command from your File menu. Instead it removes the Merge command from the File menu.
We fixed the problem in release 3.02. Please update to version 3.03.