HTML Support Limitations and Troubleshooting in Word Processing Document API

Jul 02, 2025
4 minutes to read

Word Processing Document API is not designed to fully support the HTML format. Expect HTML interpretation to be limited and optimized for documents rather than web pages. This topic describes these limitations, possible issues, and troubleshooting steps you may take when you process HTML documents. The same limitations apply to the DevExpress.XtraReports.UI.XRRichText component.

Supported HTML Tags

RichEditDocumentServer converts HTML files into its internal document model. Some HTML tags and CSS attributes have no counterparts in Open XML and RTF formats. This means that HTML documents may lose some of their formatting if you use RichEditDocumentServer to process them.

The table below lists HTML tags that the RichEditDocumentServer supports. External links are processed for inline pictures and style sheets (CSS files). The id and class attributes are interpreted for all tags, including those not listed below.

Tag	Attributes	Notes
a	dir
b	dir
background-color		The tag specifies the ParagraphPropertiesBase.BackColor property.
base
basefont	size
color
face
dir
big	dir
blockquote	dir
br	dir
center	dir
code	dir
del	cite
datetime
div	page-break-before
page-break-after
page-break-inside
background-color
border (CSS)
dir	Only the always property value is supported for the page-break-before tag.
em	dir
font	size
color
face
dir
h1-h6	align
dir	Specify a paragraph’s Paragraph.OutlineLevel property to mark text in an HTML output with H1 - H6 tags. Paragraphs with outline levels higher than 6 are exported as text enclosed in a P tag.
head
html
hr	align
color
noshade
size
width
i	dir
ins	cite
datetime
img	align
src
height
width	If the align attribute is not specified, the image is considered as inline.
li	type
value
dir
link	href
type
media
dir
meta
ol	type
value
align
dir
p	align
dir
line-height
small
span
strike	dir
strong	dir
style
sub	dir
sup	dir
table	align
bgcolor
border
bordercolor
cellpadding
cellspacing
dir
width	The dir attribute reorders table columns and applies the table indent (specified by the Table.Indent property) to the right side of the table.
td	align
bgcolor
bordercolor
colspan
height
nowrap
rowspan
text-align
valign
width	The align tag is supported in Internet Explorer only. The bgcolor attribute specifies the TableCellPropertiesBase.NoWrap property value.
The RichEditDocumentServer interprets the bordercolor attribute differently from an HTML browser.
th	any allowed
tr	align
bgcolor
bordercolor
height
text-align
valign	The align attribute is supported in Internet Explorer only.
u	dir
ul	dir

Unsupported HTML Tags

<base> tag with href attribute;
<div> tag with border, align, and float CSS attribute;
<li> tag with list-style-image CSS attribute;
<margin> tag;
<script> tag;
<tab> tag;
<table> tag with cols attribute;
<td> tab with bordercolor and nowrap attributes;
<title> tag;
!important declaration;
word-wrap, break-word, and letter-spacing css properties;
css3 shapes;
<ui> tag with type attribute.
shorthand CSS properties, such as font:

Unsupported Document Elements

The following document elements are not exported to HTML format:

Headers and footers
OLE objects

Mso-prefixed Styles

Microsoft Word and other word processing applications allow you to save HTML documents with Microsoft Office mso-prefixed styles. For example, these styles are applied when you select Web Page type in the Save As dialog in Microsoft Word. Word Processing Document API does not support these style types. To create a document compatible with DevExpress Word Processing Document API, save Microsoft Word documents in the Web Page, Filtered format.

Media Queries

Word Processing Document API processes media queries as regular CSS styles. The HtmlDocumentImporterOptions.IgnoreMediaQueries option allows you to ignore media rules in HTML documents.

C#
VB.NET

csharp

wordProcessor.Options.Import.Html.IgnoreMediaQueries = true;

wordProcessor.Options.Import.Html.IgnoreMediaQueries = True

Default Font Parameters and Formatting

Word Processing Document API uses the Times New Roman font with size 12 as default font parameters in HTML documents.

The Normal style is exported as the default style. To change this behavior, set the HtmlDocumentExporterOptions.DefaultCharacterPropertiesExportToCss property to false and explicitly set the Document.DefaultCharacterProperties.ForeColor to Black.

C#
VB.NET

csharp

wordProcessor.Options.Export.Html.DefaultCharacterPropertiesExportToCss = false; 
wordProcessor.Document.DefaultCharacterProperties.ForeColor = System.Drawing.Color.Black;

wordProcessor.Options.Export.Html.DefaultCharacterPropertiesExportToCss = False
wordProcessor.Document.DefaultCharacterProperties.ForeColor = System.Drawing.Color.Black

You can also use this API to reduce the number of span tags in an HTML document.

Troubleshooting

Try one of the following solutions if issues occur with the HTML document output or an exception is thrown:

Make sure that the HTML document does not contain unsupported tags or elements (OLE objects, headers, and footers).
Enable exceptions when debugging the project. Refer to the following article for more information: Obtain an Exception’s Call Stack
Use global policy settings to spot, analyze, and prohibit unwanted download requests. Refer to the following article for more information: Suppress Control Requests to Download Data from External URLs
Compare the export result with Microsoft Word or other word processing application. If other word processors produce a different result (apart from the described limitations), please contact the DevExpress Support Team.