Please note to make a backup of your docuent before trying any of the steps below.
This message " This is not a valid action for the end of a row " typically appears with the tables. If you are ending any sections in your document with tables, this can cause the error message to appear. To avoid this, you can add some plain text after the table. You can always set the font to the same color as the page, so the text does not appear. If you are just printing the document, you can set the text to “Hidden.”
Alternatively, the message may appear if the table is corrupt. If you recently added a table to the document, you can try cutting it and adding it to a new document to see if you are able to format your document. If the issue is a corrupt table, you can always try re-creating the table manually. Alternatively, you can keep the tables in a separate document. When you are completely done working with EndNote in your document, you can use the “Convert Citations and Bibliography > Convert to Plain Text” command. That will create a new copy of your document that is no longer linked to EndNote. You can then add the tables to this new copy of the document.
If none of the steps above help to resolve the issue then please contact Technical Support directly
1-800-336-4474 option 4 then 1
or
https://support.clarivate.com/Endnote/s/technicalsupport?language=en_US