I feel like this has probably been discussed before, but I could not find this exact issue.
When I long press home to go to recently used apps sometimes I get an error when selecting an app saying "Application is not installed on your phone." I thought perhaps this was because of the "Media area" of the memory. I went to the manage apps section and ensured that no apps were installed on the media area (no boxes checked), however I'm still getting the error. I have not moved any apps to the SD card yet.
Also if this has already been discussed if anyone could help out with the link, would be much appreciated.