there was an error when trying to save page to the server

Source: mscorlib
Type: System.FormatException
Message: Input string was not in a correct format.
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Exception data:

Stack trace:
at System.Number.StringToNumber(String str, NumberStyles options, NumberBuffer& number, NumberFormatInfo info, Boolean parseDecimal)
at System.Number.ParseDouble(String value, NumberStyles options, NumberFormatInfo numfmt)
at System.Double.Parse(String s, NumberStyles style, NumberFormatInfo info)
at System.Convert.ToDouble(String value)
at ContentFiltering.Office.Word.Filters.LocalImageAdaptorFilter.getStartMarker()
at ContentFiltering.Office.Word.Filters.LocalImageAdaptorFilter.BorderImages(XmlDocument& xmlDoc)
at ContentFiltering.Office.Word.Filters.LocalImageAdaptorFilter.Filter(XmlDocument& xmlDoc)
at XWiki.Office.Word.LocalToWebHTML.AdaptSource(String content)
at XWiki.Office.Word.ConversionManager.ConvertFromWordToWeb(String content)
at XWord.AddinActions.SaveToXwiki()
at XWord.AddinActions.SaveToServer()
at XWord.XWikiRibbon.btnSavePage_Click(Object sender, RibbonControlEventArgs e)