can't login to panel by AD users

can't login to panel by AD users

Hi,
I have installed ADManager Plus.

I can't login to panel by AD users
I add Help Desk Technicians from my AD.
when I try login to ADManager Plus it show me erro:

For input string: "unlimited"

I use
Usearname: mydomain\myusername
pass: my password


                New to ADManager Plus?

                  New to ADSelfService Plus?