Virus Alert via email - subject or content reject by outgoing email provider.

Avast Free Antivirus / Premium Security
1

The test message is always rejected by my outgoing email server, LCN.

The subject is =?UTF-8?b?VmlydXMgV2FybmluZw==?= which I presume is the issue.

Is it possible to change the subject or content so its not rejected?