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ADS Access Denied

We are sorry to inform you that your access to the ADS services has been denied. If you are consistently receiving this message, even when trying to access our top-level page, it means that our system detected suspicious network activity associated with your computer's IP address.

In order to find out what the problem may be and help us resolve this issue, please follow this procedure:

  1. Find out what your IP and proxy settings are by going here and noting the information displayed in the page.
  2. Check to see if your IP address (or any of the proxies listed in the above page) is blacklisted by going to the Project Honeypot page and entering these addresses in their search form.
  3. If the Honeypot project indicates that your IP address has been blacklisted, please follow the directions provided in the resulting page. Once your IP has been cleared, access to the ADS will be restored automatically.
The process described above solves the majority of access denial cases, but not all. In some cases, the HTTP headers sent by your browser contain information suggesting use of your own or your provider's proxy, in which case additional checks are made by our services to prevent open proxy abuse. If you are aware of such settings and have control over them, you may want to disable them to see if it makes a difference.

If you need further assistance, please forward the above information to ads@cfa.harvard.edu, and we will do our best to help you diagnosing the access problems, but please realize that in some cases you may need the help and support of your IT staff.