This can occur if your <!DOCTYPE> tag is missing in your website’s HTML code.This tag is found in the first line of a website’s HTML code.
If your tag is missing, put the following:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN” “http://www.w3.org/TR/html4/loose.dtd ">
This issue can also occur if your tag is partial. An example of a partial tag is as follows:
<DOCTYPE HTML PUBLIC “-//W3C//DTD HTML 4.01 Transitional//EN”>
If your tag is partial, please replace it with one of the following (depending on your website’s code):
<DOCTYPE HTML PUBLIC “-//W3C//DTD HTML 4.01 Transitional//EN” “http://www.w3.org/TR/html4/loose.dtd ">
<DOCTYPE HTML PUBLIC “-//W3C//DTD HTML 4.01//EN” “http://www.w3.org/TR/html4/strict.dtd ">
<DOCTYPE HTML PUBLIC “-//W3C//DTD HTML 4.01 Frameset//EN” “http://www.w3.org/TR/html4/frameset.dtd ">
Please note that solution will work only for IE and Opera only. To learn more about tag please click here.