One of my customers uses issue lists for project ticketing and after migrating from an older version of SharePoint they noticed that the emails no longer had this ID in them. It is quite important for them to have the ID easily available. So I set out to modify the alert templates.
There is no specific alert template for issue list. However, there is one for this assigned to notification email. See the MSDN article about alert templates for further reference on all of the different templates.
In SharePoint 2013 all alert templates are in one XML file located in the C:\Program Files\Common Files\microsoft shared\Web Server Extensions\15\TEMPLATE\XML directory on the SharePoint App server. The file you need is alerttemplates.xml.
As with anything located in the SharePoint root, you should not modify the original template file, but make a copy of it in the same directory and rename it, eg. alerttemplatesIssueId.xml. Then open this copy file for editing (notepad will do, VisualStudio is more colorful ;) ).
It is a long winded file. The AlertTemplate elements wrap each different template. Each has the template type set as value for Name attribute, e.g. Name="SPAlertTemplateType.GenericList".
In order to simply make the Issue ID visible in the notification email for changed "assigned to" value, find the SPAlertTemplateType.AssignedtoNotification template. Find the properties element. Remove ID from the ImmediateNotificationExcludedFields.
This will make the ID visible in the email body of this notification email. If you wish to have the ID visible in any alert a user subscribes to regarding the Issue list, you will need to remove the ID from the exclude fields of the properties in the GenericList template, since issue list does not have one of its own. Note, that all the other templates have two properties, the Immediate and Digest notification exclude fields.
This was not enough for my customer, since they wanted to have the ID also in the email subject. This can be achieved rather easily by adding the ID field variable to the subject element. The trick, especially with the AssignedToNotification template, is to find the correct place.
The ID field variable itself is added as a single tag element: <GetVar Name="NewValue#ID" />
The place to add it to, is next to the item name or list name, eg.
In the AssignedToNotification template this is crammed between two switch elements, inside the subject element. In the GenericList template, the subject element is far more simple:
This would already display the ID in the subject, but just to make it a bit more readable, you should add some HTML between the variables, eg.
Now, save your alert template. In order to get SharePoint to use this template, you need to run a little stsadm command. The easiest way is to open the SharePoint Management shell, run as admin, and then run the command:
stsadm -o updatealerttemplates -url http://<sitecollectionUrl> -filename "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\15\TEMPLATE\XML\alerttemplatesIssueID.xml"
(Note, copy-paste will probably not work for the command because of the quotation marks)
After running this command, you need to do an iisreset, and that's it. Your templates are ready and in use!