I am having the same issue, but it just recently began. I moved several apps to my sd card months ago and have been using them just fine for those 2-3 months. These apps included Firefox browser, the B&N Nook app, the Angry Birds games, and a few other games. I don't see any of these as having a widget that needs to update frequently - and they all did work fine the times I used them for the 2-3 months they were on the sdcard.
However, I noticed that after a plane trip I took two days ago, when I turned the phone back on after landing at the airport, that my apps I had moved to my sdcard were showing the generic android app icon in place of their normal one. Clicking on that gives me the error "Application is not installed on your phone."
I can go back into the Market and reinstall them and even move them to the sdcard again. And they'll work just fine from the sdcard until I do a power off/power on of the phone (I did that just to test whether the reinstall would fix the problem). After the reboot, the apps show the generic icon again and won't let me use them off the sdcard.
I can browse the contents of the sdcard through the "MyFiles" browser or other similar apps. I can see the installed apps folders there. I can listen to and copy/move/delete music files on the sdcard. I just can't use any apps I install there after doing a reboot. I travel frequently and need to shut off my phone during takeoff/landing so this will present an issue each day I fly.
Any ideas? It seems to me that the "link" or whatever it is that the OS uses to call the app into operation is broken.
My specs:
SCH-I500
Firmware 2.2.2
Baseband: S:i500.04 V.ED05
Kernel: 2.6.32.9
Build: SCH-I500.ED05
No new system updates are available as of this posting. Any and all assistance is greatly appreciated.
Thanks!