Graphics in IE only appearing as an "X in a blank box -- NO graphics"

[Craig E]

After performing some maintenance on my PC (Norton Doctor,
McAfee Clean Disk/Space Maker, etc.) I seemed to upset
Internet Explorer. ...Perhaps I've inadvertently deleted
necessary files or the settings have changed..?

Most of the graphics on most of the Web Pages now ONLY
appear as a "little red "X" in a blank box outline -- NO
graphics". ...As you can imagine, this has dramatically
altered the way Web Pages appear and almost unreadable --
virtually useless.

Anyone know the answer..? Thanks a million if you do.
-Craig E