Please bear with me, as i am still learning how to use Mantis and PHP...
While still logged into Mantis, i corrected the custom_strings_inc.php file by adding the <?php ... ?> tags, and this corrected the problem for all the plugins installed i have installed (Plugin Manager, Bugsin, Hierarchy, and Reminder).
However, when i log out of Mantis, close the browser (tested using both Firefox and IE6) then reopen the login page, the browser page is blank and the following is display in the address window:
[
localhost]
If the custom_strings_inc.php file is deleted, the login page is being displayed.
godfrey