Why does Office go through Configuration routine every time?

I have been using Windows XP service pack 2 in my system and since last week the microsoft office home and student 2007 version goes through the configuration process as well as the activation wizard when ever i start Word or Excel after starting up my system. Why does it forgets that its already been configured and activated a long time. Can anyone please tell me how do I stop this process and rectify this issue?

Actually the Windows installer engine checks if proper versions of the needed files are installed when a microsoft office program is activated. For an instance if any file is damaged or not installed properly, then Windows installer will start an Install-On-Demand to repair that particular files which is missing or damaged. Also when a user account doesnt have read permission to the registry and the subkeys that is required by the Windows installed for queries then it wont be able to determine if the program is damaged or corrupted. You could try the method which is explained for properly here -

Windows Installer-related event IDs are logged in the Application log when you start an Office program - http://support.microsoft.com/kb/911682

Try the below solution that will work properly without any issues:

1. First get the setup/configuration thing to happen, and then immediately cancel it.
2. After that check in the event viewer for error, in my case, it was telling that a file was missing.
3. Search in the hard drive or either online for that particular file and see if it is not in the wrong folder, if so then copy it and put it in the correct office folder.
4. Now try to run any office application, it will work properly.

I just resolved this issue with a Microsoft tech. Shameful that they have not made this fix known on their website! I use Vista. He had me go to 'users' and turn OFF the 'User Account Control" UAC.....that annoying pop up that asks if you really want to do what you just did!

Then he told me to open a 'run' window and here are the instructions from the e-mail he later forwarded. After spending hours on this, readign this same blog and reinstalling 7 times and system restoring 3, this fix completely stopped the whole 'configuraing' disaster.

Resolutions for the windows installer prompt, when opening Office application on a Windows Vista OS. The resolution appears to be two fold, First of all you might want to add the following registry key depending on the application for which the user gets a prompt:

Click on Start Run then type and run the following command for each respective applications.

reg add HKCU\Software\Microsoft\Office\14.0\Word\Options /vNoReReg /t REG_DWORD /d 1

reg add HKCU\Software\Microsoft\Office\14.0\Excel\Options /vNoReReg /t REG_DWORD /d 1

reg add HKCU\Software\Microsoft\Office\14.0\Outlook\Options/v NoReReg /t REG_DWORD /d 1

reg add HKCU\Software\Microsoft\Office\14.0\PowerPoint\Options/v NoReReg /t REG_DWORD /d 1

reg add HKCU\Software\Microsoft\Office\14.0\Access\Options/v NoReReg /t REG_DWORD /d 1

reg add HKCU\Software\Microsoft\Office\14.0\Publisher\Options /v NoReReg /t REG_DWORD /d 1