The SELECT :

SELECT

1 as Tag,

null as Parent,

[NewsTitle],

[NewsSummary],

LEFT(DATENAME(dw, [NewsDate]),3) + ', ' + STUFF(CONVERT(nvarchar,[NewsDate],113),21,4,' GMT')

FROM [sd_News] WHERE [IDChannel] = '11'

With the FOR XML :

SELECT

1 as Tag,

null as Parent,

[NewsTitle] as [item!1!title!ELEMENT],

[NewsSummary] as [item!1!description!CDATA],

LEFT(DATENAME(dw, [NewsDate]),3) + ', ' + STUFF(CONVERT(nvarchar,[NewsDate],113),21,4,' GMT') as [item!1!pubDate!ELEMENT]

FROM [sd_News] WHERE [IDChannel] = '11'

FOR XML EXPLICIT

After some tests, it seems that the problem occurs when the HTML data store in the column NewsSummary is very important.

Regards.