When I send a reply into Web Crossing via email, it comes back with:

"For your protection, this mailing list does not allow unauthenticated posts by email.Please re-post through the Web. Go to <http://yoursite/WebX?xxxxxxx>. Then you can copy/paste this message into your Web browser."

A number of situations can cause this.

• If you are still running 4.1 (no longer supported) UPGRADE/UPDATE!!! 4.x builds prior to December 2001 did not remove guest user email addresses from an internal authorization email table.
  
• First, you must make sure that the parent folder of this discussion has been set up to permit replies via email. Navigate to the folder, EDIT it, select the "Email list settings" link and make sure you have "This folder is an email list -- users can post by email" checked.
  
• Make sure that there are NO other users with the email addresses or aliases that are shared with any other account. If this is ever the case then web crossing has no way of knowing who is sending in the email and will block the posting. This includes:
  
  
  
  
  1. The default email address based on the site's default domain
     
  2. The contact email address set when the user registered
     
  3. Any number of email aliases in the user preferences.
     
  4. Guest users who have posted using the email addresses of a registered user.
     
  
  One way to see if an address has a duplicate or not is to attempt logging in using the email address instead of username. Web Crossing allows logging in this way, but it only works if there is a single unique email address.
  
• If a discussion was posted by a user who had an email address or alias that is the same as one that now exists in the system Web Crossing will not permit the post to go through. If those posts are deleted, then the problem will go away.
  
• Similarly, if a *message* was ever posted by a user who had an email address or alias that is the same as one that now exists in the system, even if that message and user were deleted, Web Crossing will not permit the post to go through. Why? Because messages are not actually "deleted" per se (like entire discussions are), they are marked to not be shown. Because of this the posters original identity and email still exist in the database.
  
• Check your access lists. Have you set them to read-only? Is this user or users provisional in status for the whole system or set to read-only permissions?