Demo login with problem

Hello,
I am trying to logon using a newly created demo login, but NinjaTrader returns me the message "Unspecified Login Error (Logon failed)". I am using NT8 (the last version downloaded from downoload area), and configured the demo account as CQG. I also contacted CQG for they to check the account and they answered me to contact you NT support. My Windows is 10, 64-bit.
Thanks in advance.

Please write a note to our Platform Support team at PlatformSupport[AT]NinjaTrader[DOT]com and we will be glad to provide assistance with this inquiry. Please also include a link to the forum post.

I have just sent the message to there.

Thank you very much.

Thank you very much.