Microsoft has acknowledged a new bug that affects Windows 95 and NT 4.0 users who have Internet Explorer 3.x or 4.0 and PowerPoint 95/97 on their system. A fix for the bug was posted to the Microsoft Web site on Friday. The problem involves a potential misuse of a PowerPoint 95/97 feature that allows an application to be run over the Web from within PowerPoint without first warning the user. The problem occurs in Internet Explorer only. The fix will prompt the user before any PowerPoint file is opened from within Internet Explorer