About 3 days ago, I had run what I thought was a thorough defrag of all my drives and today I decided to do the same and it seems to be defragging the drives as if it had never been done before. It took about 5 hours to run the defrag a couple of days ago and I'm looking at an even longer defrag time today. Is this normal?
it would help if we knew what sort of defrag was done initially and what sort is being done now.
other factors that come into play would be, how much usage has the PC had in the interim?, any large files changed like pagefile, restore points, Windows Updates, downloads, DVD burning etc?
how many Users on the PC?
your Windows version?
has any other 'maintenance' processes run, potentially screwing up the layout organised by DF? things like Windows inbuilt defragger, your security software may do cleaning, any other cleaning software, any scheduled cleaning tasks etc?
You may need to run CCleaner first to remove junk files which can help speed up a defrag.
Also if you have another defrag program running automatically such as the one built into Windows it can undo what Defraggler did without you even knowing it happened because it does so in the background. Therefore when you run Defraggler again it has to undo what the Windows defrag did, and since Defraggler is rather thorough it can take a long time to complete. It's because of different algorithms used in different defrag tools, i.e.; how they defrag and determine file placement.