Xp sp2

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Install SP2.
If you experience problems come back and report exactly what difficulties you are having, what you have tried and what error messages you are receiving. Then we will be able to help you better. :-)
Ed

Per the advice on the first answer that is obviously what I will do. Though at this time I will clarify. I never actually recived any errors. the programs just did not open. The screen blinks like you are opening something, but it never actually opened. And there was no sign of it running in the Task mgr.

Reading this article ma be of help
Details
Windows XP SP2 will dramatically improve the default security configuration for XP in nearly every area from e-mail to Web browsing to increased protection against the ubiquitous buffer overrun. But, all of these security improvements won?t come without some considerable pain. ZDNetUK reports that Microsoft admits that as many as one application in 10 will experience problems due to the upgrade (I consider that a conservative estimate).

Here are some of the most important security changes that are part of XP SP2:

The Internet Connection Firewall is now enabled by default, which should improve security for SOHO users. However, in a corporate environment it could cause problems for users trying to connect to network resources. The firewall will also now activate much earlier in the boot cycle, even before the network stack is enabled. On shutdown, it will now remain active until after the stack is disabled.
The Messenger service is now disabled by default.
A pop-up ad blocker has been turned on by default.
A unified security application called the Windows Security Center has been added (for more information on this feature, see this News.com article). It is supposed to bring all of the most basic security configuration information into one easy-to-manage place that will show whether your firewall is enabled, if your antivirus software is working, and if you have the latest software updates installed.

As per the info above most problems that are related to SP2 are due to the increased security configuration.
Your symptoms do not sound like they are a result of the service pack. I have never heard of being uinable to open notepad before. It is much more likely you are infected with some malware.
Check your task manager and msconfig for items that you do not recognise and remove them.
If you are not having any joy I would suggest reinstalling windows so you can be sure you have a clean system. Ensure you enable a firewall before connecting to the internet to download updates.

Hope this helps :-)

before installing SP2 I get all updates from Mircosoft for PCs that have been in use for a while,
then install SP2 .
for new build/ fresh rebuilt PCs I install a fresh copy of XP/SP1 than install SP2 then install other software.

I have had no problems doing it this way.
I have done this on over 10 PCs/Laptops
and have not had any problems with them.

Other techs at work have not done it my way and they have problems, blue screening and others problems.

Good luck

Excuse me for taking so long to reply. but the computer works fine under SP1. I have since tried installing SP2 under Administrator with the same results. I just checked quickly So I do not know what all doesn't work. But notepad will not open The windows security alerts in task bar doesn't work. Cannot open anything in Administrative tools... I guess I'll have to do the clean install .When I get around to it. Thx for the suggesttions

Well since i really did not want to do a clean install. i guess that is what I will have to do.

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