Problem with security mode and grid application

Hi!
I have a problem when i activate the security mode.
I have a login that assign permits to apps end build the menu. If i activate the security mode in a grid, it is showed perfectly but i can’t navigate into its (i can’t go to nex the pages and every type of seach don’t work). It continues to load data but it doesn’t stop.
Why? it’s very strange.
Thanks to everybody

Michele