a very peculiar problem indeed..

my stuffit expander doesn't work. everytime i try to open up a .sit file, it creates the folder- but nothing inside.
this has only started happening, i don't know what triggered it.
so any solutions?

Redownload stuffit and reinstall it. That'd probably be easiest.

Otherwise...
1. Repair Disk Permissions (do this from the disk utility which is found in your harddrive/applications/utilities folder
2. Run everything this program can do: http://www.jimmitchelldesigns.com/yasu.html
(I also recommend running it once a week for good general maintenance).
3. If those don't work, your best bet is to just reinstall

i've done step 3 but it didn't fix it.
and can you please elaborate 1 further..thanks

what version are of stuffit are you using? i'm running 10 but sometimes it doesn't work and i have to revert to 9

stuffit expander 10
and uhh..if you're suggesting alternatives, i'm a real cheapskate so freewares please
so wheere do you get 9?

I've also had problems with version 10.
I reverted to version 9 and haven't had any problems with it.
Where to find Stuffit Expander 9?
Try this link: http://www.allume.com/downloads/files/StuffItStandard9.0.1.dmg
This is a link which connects you right to the download, version 9.0.2 I believe.