OS X shows "Sign in to use this application on this computer" dialogs when opening App Store applications After a reboot of OS X, I often need to re-enter my Apple ID password in order to use the apps I bought in the App Store. Sometimes I have to re-enter my password only once and all the apps work (until the next reboot), but often I have to repeat this for every single App Store app I open.

For example, I might get this dialog the first time I launch Reeder after rebooting OS X:




  Sign in to use this application on this computer
  
  “Reeder.app” was purchased using App Store on another computer. To install “Reeder.app” on this computer, sign in using the Apple ID and password used to purchase it.


I have tried to delete the following files:


~/Library/Caches/com.apple.appstore
~/Library/Caches/com.apple.storeagent
~/Library/Cookies/com.apple.appstore.plist
~/Library/Preferences/com.apple.appstore.plist
~/Library/Preferences/com.apple.storeagent.plist


But this didn't solve the problem. I have reinstalled all the apps, but that didn't help either. Moreover, I have done a clean install of OS X (for another reason) but I still have this issue with Mac App Store apps. Could this be related to my hardware or Apple ID?

Is there anyone who has had a similar problem or someone who might help me?
This same problem plagued me for months.  Any non-free mac store app would ask for a user name and password to access with the dialog box shown above.  When I lacked internet access, the app simply wouldn't load at all.  

After trying all sorts of solutions - deleting the apps and reinstalling, re-entering passwords and credit  card numbers in the app store itself, etc., I finally found something that solved the problem:

I reinstalled Mountain Lion from the rescue partition installed on my hard drive.  While this takes some time (about three hours), it isn't as drastic as it sounds.  All my apps and files and passwords were intact after the reinstallation, and for the past two weeks I haven't had to re-enter any mac app store passwords for the apps I've purchased.

here's a link to a Macworld article that explains the process of reinstalling the OS:

http://www.macworld.com/article/1167870/hands_on_with_mountain_lions_os_x_recovery_and_internet_recovery.html