If the Event object has associated a comment or a comment's description, a tooltip appears if the cursor is over the event's date.  Use the ComentTitle to defines the title for the event's comment. Use the properties like: ToolTipDelay, ToolTipPopDelay, ToolTipFont and ToolTipWidth properties to specify the options for the tooltips. Use the CommentBackColor property to specify the color being used to mark the dates with comments.

The tooltip supports the following HTML tags:

• <b>  bold </b>
• <u> underline </u>
• <s> strikeout </s>
• <i> italic </i>
• <fgcolor = FF0000> fgcolor </fgcolor>
• <bgcolor = FF0000> bgcolor </bgcolor>
• <br> breaks a line. 
• <solidline> draws a solid line
• <dotline> draws a dotted line
• <upline> draws the line to the top of the text line
• <r> aligns the rest of the text line to the right side
• <font face;size>text </font> displays portions of text with a different font and/or different size. For instance, the <font Tahoma;12>bit</font> draws the bit text using the Tahoma font, on size 12 pt. If the name of the font is missing, and instead size is present, the current font is used with a different size. For instance, <font ;12>bit</font> displays the bit text using the current font, but with a different size.
• & glyph characters as &amp ( & ), &lt ( < ), &gt ( > ), &qout ( " ), &#number, For instance, the &#8364 displays the EUR character, in UNICODE configuration. The & ampersand is only recognized as markup when it is followed by a known letter or a # character and a digit. For instance if you want to display <b>bold</b> in HTML caption you can use &lt;b&gt;bold&lt;/b&gt;

The following sample shows how to attach a comment to "a day before yesterday" date:

Private Sub Form_Load()
    With CalendarCombo1
        With .Events.Add(Date)
            .CommentTitle = "Just a title"
            .Comment = "This is a bit of text that should appear when the mouse is over the date.<br><r><dotline><upline><b><fgcolor=0000FF>Exontrol ExCalendar</b></fgcolor>"
        End With
    End With
End Sub