You can use the EmailSubject property to specify or determine return the email subject line of a hyperlink to an object, document, Web page or other destination for a command button, image control, or label control. Read/write String.
expression.EmailSubject
expression Required. An expression that returns one of the objects in the Applies To list.
Remarks
The EmailSubject property is a string expression representing the subject line within a file (UNC path) or Web page (URL).
You can set the EmailSubject property by using a macro or Visual Basic for Applications (VBA) code.
You can also use the Insert Hyperlink dialog box to set this property by clicking the Build button to the right of the property box in the property sheet.
Note: When you create a hyperlink by using the Insert Hyperlink dialog box, Access automatically sets the EmailSubject property to the location specified in the Subject box of the E-Mail Address tab.
When you move the cursor over a command button, image control, or label control whose HyperlinkAddress property is set, the cursor changes to an upward-pointing hand. Clicking the control displays the object or Web page specified by the link.
To open objects in the current database, leave the HyperlinkAddress property blank and specify the object type and object name you want to open in the HyperlinkSubAddress property by using the syntax "objecttypeobjectname". If you want to open an object contained in another Access database, enter the database path and file name in the HyperlinkAddress property and specify the database object to open by using the HyperlinkSubAddress property.
The HyperlinkAddress property can contain an absolute or a relative path to a target document. An absolute path is a fully qualified URL or UNC path to a document. A relative path is a path related to the base path specified in the Hyperlink Base setting in the DatabaseNameProperties dialog box (available by clicking the Microsoft Office Button 
Note: When you follow a hyperlink to another Access database object, the database Startup properties are applied. For example, if the destination database has a Display form set, that form is displayed when the database opens.
