Third-party virus scanners sometimes detect the ClamAV signatures as viruses and move them into quarantine.
Please define exceptions for the following directories in your third-party virus scanner:
C:\Program Files (x86)\Common Files\JAM Software\ClamAVInABox
You can train the Bayes filter with multiple emails at once. To do this create a POP3 account in your Exchange Server (e.g. named trainSpam) and setup an account in SmartPOP2Exchange pulling emails from that account.
Add a rule for this account applying for any message with the action to train the Bayes filter with spam. To use this account for training attach all spam emails as attachments to an empty email and send it to the trainSpam account. SmartPOP2Exchange will detect the empty wrapper message and only trian the attached messages.
The same can be done with a "trainHam" account.
Your Exchange Server returns this error if the sender address is blocked by the sender filter of the Exchange Server: https://docs.microsoft.com/en-us/Exchange/antispam-and-antimalware/antispam-protection/sender-filtering?redirectedfrom=MSDN&view=exchserver-2019
Please deactive this filter or at least exclude SmartPOP2Exchange from ever being rejected.
SmartPOP2Exchange only deletes emails from the POP3 server if it has been successfully sent to the destination SMTP server.
If the SMTP server refuses the email more than 3 times it will be saved to the folder "<backup path>\DeliveryFailure" and a summary email will be generated and tried to be delivered instead.
This "error message" is caused by greylisting solutions.
For example, if you are using ESET for Server, even if you disable anti-spam capabilities in its configuration, it will not be greylisted.
To disable greylisting, the Exchange Server Transport Agent must be disabled by ESET: (in the Exchange Server PowerShell)
Disable-TransportAgent -Indentity "ESET FilterAgent
This is a limitation of the receive connector of the MS Exchange Server. It only allows a certain number of simultaneous connections from a single IP. The default value is 20.
You can query the value for your receive connectors on the Exchange Powershell:
Get-ReceiveConnector -Identity <connectorname> | fl MaxInboundConnectionPerSource
To change the value you can use the following command:
Set-receiveconnector - identity "CONNECTOR_NAME" -MaxInboundconnectionPersource 100
Please restart the Microsoft Exchnage Transport service after changing the values.
It seems you are missing the correct OLE DB Provider.
To correct this you have to go to this website from Microsoft and download the Access Database Engine 2010 in 32-bit.
Make sure you download and install the 32-bit version since the database connection is not supported with the 64-bit version.
The requested name is valid, but does not have an Internet IP address at the name server. This is not a temporary error. This means another type of request to the name server will result in an answer.
No such host is known. The name you used is not an official host name or alias. This is not a software error, another type of name server request may be successful.
Check that you have a name server(s) and/or host table configured. If you are using a name server(s), check whether the server host(s) are up (e.g. try to ping the server(s)). You could also try to resolve another host name you know should work, to check if the name resolution server application is running.