How to add SMTP address to exisiting E-mail address policy using Exchange 2007 Management Shell

You may face difficulties if not used to of Management shell for exchange and you are more confortable with Management console.
If you want to add additional smtp address in exisiting smtp policy and addition address formation is not present in default format in EAP. e.g. Alias+somecharacter@domain.com.

You can following to achive your goal.
Set-EmailAddressPolicy -Identity "Name of policy" -EnabledEmailAddressTemplates 'SMTP:%s.%m@domain.com','smtp:%m+test@domain.com'

Here make sure you are including all the addresses in your existing EAP. Set-EmailAddressPolicy will replace the existing e-mail addresses as well. Also here capital SMTP defines the primary SMTP address for the EAP and rest are secondary address. Make sure you putting X400 address as well is it existing there in list of EAP.

For X400 you can add one more string.
X400:c=US;a=adminstrativegroup;o=organ