I import Word Document for the same document "2015 script PRD.docx",
First time, I can success to Import Word Document for "2015 script PRD.docx", with "Import as a new page in the current space"(Where to import), "Rename imported pages if page name already exists"(Title conflicts). See the first screenshot.
Second time, for the same document "2015 script PRD.docx" (I didn't change anything), I want to replace it with the old one, so I Import Word Document with "Replace 2015 script PRD"(Where to import), "Replace existing pages with imported pages of the same title"(Title conflicts), see the second screenshot. I wait several seconds, then got a blank page with no explanation of why.
I checked atlassian-confluence.log, and found the error:

......
Caused by: com.atlassian.confluence.content.render.xhtml.XhtmlParsingException: The XML content could not be parsed. There is a problem at line 1236, column 62. Parser message: Unexpected close tag </strong>; expected </em>.
at [row,col

{unknown-source}]: [1236,62]
......
Caused by: com.ctc.wstx.exc.WstxParsingException: Unexpected close tag </strong>; expected </em>.
at [row,col {unknown-source}

]: [1236,62]
......

My version of Office is 2010. This issue occurs only for a specific word file, not all word files. Please see my attachment TestWord.docx, you can reproduce the same issue.