Why can't I run the Control Panel Add/Remove Programs applet under Windows 2000 and later?

A. The Control Panel Add/Remove Programs applet might stop running if your system is missing some required registry entries. To resolve this problem, you must add the necessary entries to the registry by performing the following steps:

1. Start a command session by going to Start, Run and typing

   cmd

2. Enter each of the following commands (click OK to each confirmation that appears):

   regsvr32 mshtml.dll
   regsvr32 shdocvw.dll -i
   regsvr32 shell32.dll -i 

3. Close the command session by typing

   exit 

You should now be able to start the Add/Remove Programs applet. If the applet still won't run, you might be missing a file; to check, use the system file checker (SFC) to check for and replace missing or corrupt files by performing the following steps:

1. Start a command session by going to Start, Run and typing

   cmd 

2. Enter each of the following commands (the system might prompt you to enter the installation media during this process):

   sfc /purgecache
   sfc /scannow 

3. Restart the computer.