I'm not sure I got this in the right place, but mods can move it if I'm wrong.
I signed up for a reseller hosting account on a shared server. The people I went with had crappy service, crappy support, and were down every other day. After a couple of months like this, I switched all of my customers over to a dedicated server and have since had no problems.
HOWEVER, one of my customers setup a mailing list through CPanel. Some mail sneaked through during the transition and is now waiting for authorization on the old shared server before it can be sent. The mail is old, but it keeps bombarding my customer with DAILY reminders to authorize the email. The customer is looking to me for answers.
I went to my hosting company and VERY POLITELY asked them to delete the mailing list so my customer would stop getting the email. Their response was that they deleted the account, that it was old emails being sent and to give it time and they would stop. Three weeks later I sent another email and said they never stopped and if they could please remove the messages or do something to make it stop. I pasted in the headers to prove that it was coming from their server and the date was well after we canceled the account.
My host only allows you to contact them through a webdesk(perldesk). They do not do email, phone, fax, nothing. Whenever I submit a post that tells them I still have this problem, I login three hours later and the post is deleted.
HOW do I get my OLD host to have their server stop sending these annoying reminder emails????