Follow suncar's instructions from his post on 7/12/11. Go to Settings->Applications->All, and select Acer Content Folders. Press "Clear Data," and that should reset the folders. You'll need to add the content back. Personally, I think the content folders are too clunky, and instead just add apps to the various home screens, grouped by category.
Sorry i can't tell you for sure how to fix that which is a real bummer cuz i have only had mine ( well this one ) for a couple weeks but hopefully on the 27th when we get the update of ICS it will fix it.. If not i would suggest you one of the webpage links on your home page top right side and go to acer home page and go to tech support. I would think they would be able to help you out.. Best of luck.