Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have a Windows Server 2003 SP1 machine that was service packed to SP2. If I now add additional components such as IIS to this machine, do I need to reinstall SP2?

If Windows handles this for me, how does it do so?

share|improve this question
up vote 6 down vote accepted

No, it's not be necessary in Windows Server 2000 and later.

When you install a service pack the Layout.inf file is updated, which makes sure that the updated version of the necessary files are used. If the updated file cannot be found in the source location of the service pack files, the user will be asked for the source of the service pack files.

The source location is stored in the following registry key:


See this Microsoft support article: Not Necessary to Reinstall Windows 2000 Service Packs After System State Changes

share|improve this answer
Note: Hotfixes do not update the Layout.inf file. Therefore, if you install a hotfix and system state changes occur, you may need to reapply the hotfix. – splattne Jul 6 '09 at 12:34

You can use the windows update in custom mode to see if there are any updates after installing the new component. It's scan should detect everything installed and make the recommendations for you.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.