We don't filter outgoing emails. But if we detect some spamming activities, not only we filter emails, but we will immediately disable such user accounts. So in your case, I believe it is your email server that does filtering. Please try some other emails as well. It seems a lot of free email service providers now put emails received from new email accounts to junk mail folder.
Also, due to some spamming activities by our users, some ISP may temporarily filter our emails. In this case, you might want to contact your ISP about the problem, telling them DriveHQ is a reponsible email service provider -- we strictly forbid any spamming activities. If we receive complaints about our users engage spamming activities, we will disable their accounts immediately. There will be no warning.