This is due to a bug in a Microsoft dll used by SendBlaster, which has not been corrected by Microsoft yet. It is caused by the <!DOCTYPE…> tag in the opening part of the page, just before the <html> tag.
In order to avoid the error, before importing the page open it with any text editor (Windows Notepad is ok) and remove the <!DOCTYPE…> declaration (even better, remove anything before the opening <html> tag).
