Hi @dsanchez ,
allow unsecure apps in Google is not good for your account security.

My suggestion is to compile the Google account with all yours information possibile!
Be sure you have recovery options than I suggest to activate the 2 step verification and to generate and save backup codes.

Once done please generate on Google a specific password for app than use this password to setup your Gmail account in UVdesk.

If the issue persist please confirm what string you have inserted in the host field in email settings, on UVdesk.