Can't login to Mac App store I have an iMac with Mac OS X 10.8 (Mountain Lion). When I open the Mac App store, and try to download an App, it asks me for the login. When I enter my Apple ID's email and password and click login, the button become gray for a moment, and then asks me for the credentials again. There is no error message displayed. The email and passwords are correct, since if I try an incorrect password it tells me that it is wrong.
I've solved installing the manual updates for Mountain Lion from here, and then it began to work normally!