If this is a recent event: Click START button/All Programs/Accessories/System
Tools/System Restore. Opt to: Restore My Computer to an Earlier Time, then click the NEXT
button. The next window in the wizard will be divided into two panes, a calendar in the
Left pane, and Restore Points for dates on that calendar in the Right Pane. The dates on
the calendar which contain Restore Points will be in BOLD font. Select a bold date as
close to the present, but PRIOR to the problem. Then highlight the Restore Point for that
date in the Right pane, and continue with the wizard until your system reboots, and you
get the message that your system has been successfully restored. Since the Windows
Registry which has all of the program associations will be replaced with an earlier
version which has the correct program associations, hopefully your problem will be quickly
solved. But, any software, or updates, that were installed AFTER the date of that Restore
Point will have to be reinstalled.