Soemtimes the files in Outlook become fragmented and need to be put back together. When you open Outlook, the drive has to search for every part of the program including all your emails to open the program. Delete some emails(if you have alot). With Firefox, delete the temporary internet files. It will load much faster.
Certain programs load very slowly at random times. When they load properly, the red drive-access light flashes and blinks for a few seconds, then the program loads. However, at times (no pattern discerned yet) the red light will stay on and the program will take nearly a full minute to load. This usually occurs with Outlook 2003 and Firefox (the programs I use most frequently), but also with other programs. I have cleaned the registry, checked for viruses and spyware, and analyzed the drive itself - all ok.
I am running windows xp home (sp2) on a P4, 2.0 ghz machine. The drive is a Samsung SP8004H 80 ghz drive. Belarc smart status says that the drive is healthy.
Any thoughts or suggestions would be gratefully received.

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