Currently I use The Bat! version 9.4.5 64 bit. Operation system is Windows 10. My problem is that The Bat! does not send my messages from my two accounts (email@example.com) created by my internet provider ten years ago. Error message: Message has not been sent. Server reply - 5.1.8 Message rejected: Access denied due to spamming (vade) - code_501
Sometimes it seems that messages have been sent, they are stored in "Sent Mail" folder, but the recipients never receive those. We use these two accounts relatively rarely. I think we can exclude spamming. I have made also virus check up, without any result. There is no spesific antivirus software installed on my computer, only Windows Defender operates.
I have set up five accounts in The Bat! (3 of them with @freemail.hu, 2 of them with @t-online.hu) and this problem only occurs with @t-online accounts. Receiving messages is ok for all accounts. At the same time it is very interesting that forwarding messages also ok. So if I receive a message to any @t-online accounts I can forward them and recipients receive those without problem.
I have also tested sending messages with an older The Bat! version 184.108.40.206 32 bit, installed on a newly installed Windows7. @t-online.hu accounts did not operate there either. Error message: Message has not been sent. Server reply - 4.7.1 <firstname.lastname@example.org>: Realay acces denied
On my computer with Windows 10 I have also installed Mozilla Thunderbird (latest version). t-online accounts work properly and sending messages is ok. I have not changed the preferences of The Bat! SMTP, POP3 for ten years. This error occured suddenly.
I have also contacted my ISP (telekom.hu), but unfortunately they are not able to help to solve this issue.
Do you have any idea how I could solve this problem?
Your provider should definitely be able to help you. Ask the helpdesk person to escalate your request to a higher level.
When mail is rejected due to spamming, you may have sent too many messages (or CC:/BCC:s) during a single session or during a certain period of time. Or, perhaps more likely, your account has been hacked (password broken) and abused by a spammer.
Have you googled the error message that you received? When I do, I see several topics in Hungarian forums come up. I don't understand Hungarian, but maybe there's some useful information there.
PS: (edited to add..) Does the provider offer webmail? I'd try logging into that and sending a message there, maybe that will produce some more useful information.
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