defaults to "Disabled" again

Hi, i need a help in this error..
this is what i did..

1. create content type : mobile
2. create new mailhandler (sukses to retrieve)

the problem is

1. in content type the mobile wont set the inline setting to another option other than "disabled".
2. mailhandler success to retrieve the email from my email, but can not posting it, i got this error message to my email
The e-mail address xxxxx@gmail.com may not create mobile items.

did i missed something ?? please help me... thanks