I can not download attachments through Web Access.

This is due to the fact that by default Internet explorer tries to cache secure web pages to your hard drive. As a security precaution Web Access does not allow this to happen. You can correct this by making the following change to Internet Explorer.

Open Internet Explorer and choose Tools, Options

Then select the Advanced tab and scroll down to "Do Not Save Encrypted Pages To Disk" and make sure the box is checked.

This should Correct your issue.