I have a MT4G running 2.2.1 rooted I have been having this problem for a long, long time. I'm at my wits end. If I remove the SD card, plug the phone in to the PC, shut down, or restart then the phone seems to forget how to access apps that are on the SD card. They show up on my home screen as the generic android icon(all of them the same) and don't appear at all in the app drawer. Apps not on SD work fine. I can go into Astro and see the files, all of them. I can open videos, music, pictures, etc. that are on it. But if I try to click on an app that is installed to it, it says "Could not launch the requested activity." App Manager shows the apps, but with generic icons and no info and all apps show computing instead of sizes. Settings>SD Card shows the card & the sizes but won't unmount. On top of that, it won't let me install or uninstall any apps unless I remove the SD Card. Sometimes even when the SD card apps are showing up, I still can't install apps. I've been at this for months now. Here's my post on here from back in July... http://androidforums.com/t-mobile-mytouch-4g/370666-sd-card-issues-appear-contagious.html I have tried EVERYTHING every single responder to previous posts( here and elsewhere) has suggested. Pull the battery, pull the SD card, pull the sim card, unmount(would freeze and not do anything), reset, format, different SD cards in this phone(found those apps fine that I also had), this SD card in other phones(found it fine, but only the apps that that phone also had), This SD card in the PC with no phone(found it fine), mounting it through recovery, fixing permissions, deleting and reinstalling things, EVERYTHING! I am so far beyond frustrated at this point I'm going insane. I can get the apps back after dozens of tries of pulling the battery, pulling the SD, rebooting, shutting down, etc in various orders and sometimes it takes days to get them back. But to then say, "OK they are back I'm never restarting again," is unrealistic and then of course apps stop installing/uninstalling and I have to reboot. And poof, gone again! :-/ I have everything thoroughly backed up with Titanium Pro and I did a Nandroid backup before doing a factory reset, but my god was that annoying having to redo everything, and it didn't even work. I've uninstalled apps individually to see if it was a specific app. I've done the reverse and uninstalled everything and reinstalled one at a time to see if one triggered it, and it kept happening randomly, never twice after the same app. So the only conclusions I have been able to form are that it's not any of the apps, and it's not the SD card itself. Someone please, please put me out of misery and give me a new solution!