To Change the default text style of the new email editor screen you need to modify the following file on the CRM server: (Please make a copy of this file before any changes are made)

C:\Program Files\Sage\CRM\CRM\WWWRoot\Fckeditor\fckconfig.js

If you open this file up in a text editor e.g. in notepad or wordpad and within this file look for the following section:

// This will be applied to the body element of the editor

FCKConfig.BodyId = '' ;
FCKConfig.BodyClass = '' ;
FCKConfig.DefaultStyleLabel = '' ;
FCKConfig.DefaultFontFormatLabel = '' ;
FCKConfig.DefaultFontLabel = '' ;
FCKConfig.DefaultFontSizeLabel = '' ;

You can update the FCKConfig.DefaultFontLabel value to be one of these supported font formats:

 'Arial;Comic Sans MS;Courier New;Tahoma;Times New Roman;Verdana' ;  

For Example:
FCKConfig.DefaultFontLabel = 'Verdana' ;

You can also default the Font size (FCKConfig.DefaultFontSizeLabel) to one of the following values:

For Example:
FCKConfig.DefaultFontSizeLabel = 'medium' ;

Save the changes, then go to the New Email screen and the new defaults you have set should be displayed when using the editor.