I suspect it is a firewall issue.
KM-000000018149 says that this error means that there is a firewall in play and that the client was able to successfully get through the firewall, but the response back from the server is being blocked by the firewall. Have the end user consult with their firewall Admin. on the rules they have in place on the firewall. They need to allow for the response back to the client to be let through the firewall.
Is your client installed on a remote machine? If so, try installing a Remedy User on the same ar server and see if it will connect successfully. Other than this, I suggest you check AR log files (arerror.log, armonitor.log, etc.)
At times, the authorization issue can make this error code to popup. If it’s the reason behind it, it’s easy to fix. To do it, open Settings options, and check the box ‘My server requires authentication’. Once done, try to send the email again. It should resolve the socket 10060 error on PC.
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