Problem to detect all computers. 1 detected = 1 disappears. Only 65 items no more.

Problem to detect all computers. 1 detected = 1 disappears. Only 65 items no more.

Hello,
 
I have a problem to detect all computers.
When I detect 1 and another disappears.
I can have only 65 items no more.
 
I use the version 8016 and all computers have the last agent 1.12.
 
Can you help me ?
 
Thank you in advance.