hi
i have the same problem
i turn on the n900
go to app manager
i can update, install and remove apps but i have too stay in application manager
so for example
i instal a app, it loads again the list with the apps and i can install again a app. but if i leave the application manager. i;m not able too install,remove, or update again. for that, i need to turn my phone off and on.
when i have left app manager and i go back, there are no catalog's. all of them are gone. when i look at error report, he says unable to lock 2314 or 1516
so whats the fix?

sorry for my englisch, im dutch