Invalid receiver
If the author instance tries to publish content to a public instance without a valid license or invalid edition, the following error appears in the log:
Invalid receiver. Either your public instance is the Community Edition or the DX Core license is invalid.To resolve this issue, see the section on updating a key on the License page.
In some cases, your license is valid but you have different Magnolia versions running in the Author and Public instances.
In this scenario, check the value of the /server/filters/multipartRequest/@enabled parameter.
It must be set to true.
In other circumstances, you may need to set the parameter to false, for example to get REST calls to work with attachments. If this applies to your case, use a bypass:
<sv:node xmlns:sv="http://www.jcp.org/jcr/sv/1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" sv:name="skipRestCall">
<sv:property sv:name="jcr:primaryType" sv:type="Name">
<sv:value>mgnl:contentNode</sv:value>
</sv:property>
<sv:property sv:name="class" sv:type="String">
<sv:value>info.magnolia.voting.voters.URIStartsWithVoter</sv:value>
</sv:property>
<sv:property sv:name="pattern" sv:type="String">
<sv:value>/.rest/</sv:value>
</sv:property>
</sv:node>