I am a reseller, so please forgive me for posting here if this area should only be for server owners. But I'm now very desperate.
Every morning I have to delete the Mail folder of each hosting account I host to clear out thousands of Mail Delivery System return emails. Each of these emails, inturn, holds hundreds of notices inside, saying that mail has failed.
Clearly there are maybe hundreds of thousands of emails being sent every 24 hours from some accounts inside my reseller account - including the reseller domain as well.
But these returned emails have the sender as my hosting client's account on the server and the recipient is also the hosting client's account on the server.
I have all unrouted mail set to :blackhole: in mostly all my hosting accounts but when its from the account itself, it appears to accept it.
1. Somehow stop the ability for the server I'm on from being exploited like this? And if so, will the booking/feedbakc forms on my hosting account's websites still work?
2. How do I get :blackhole: to work to delete ALL unrouted emails?
This is a massive concern as it pushes all my hosting accounts over their limit so they can not receive legitimate emails as well as uses MASSIVE bandwith and space.
One of the many emails being sent is advertising "Cyalus" - a Viagra alternative - so if you are getting these emails, you now know where they come from. If anyone knows how I can get in contact with the thieves that are doing this, please let me know.
I have replaced all cgi mail form scripts on every hosting account I have, hard coding the addresses, I do not believe this is the problem.
I have sent numerous support requests to the operation that hosts my reseller account (who owns/runs the server), they are a very professional and helpful group, but this time I feel this problem may have them stumped as well. Fixing it would save them enormous bandwidth costs.
Any help would be VERY extremely appreciated.
P.S. Please do not take this as a complaint about cPanel. Your cPanel product is absolutely first class and it's a nothing short of a joy to work with (from a resellers point of view anyway) and besides this email problem may have nothing to do with cPanel - I just don't now.