IE : Unable to download * from *. Unable to open this Internet site. The requested site is either unavailable or cannot be found

Question

I have an issue with my website and IE. I have a file Document.ashx that becomes a document from my database depending on the parameter passed in the query string.

The file works if:

• You're on my website and click a download link.
• You access anything on my site and paste the URL into the address bar and access it.
• You've already access the document link once before, even if it did error.

It doesn't work if:

• You've not accessed my site with the current IE open and paste the link in the address bar. It displays the following error:

Windows Internet Explorer

Unable to download Document.ashx from MyHostName.

Unable to open this Internet site.

The requested site is either unavailable or cannot be found.

Please try again later.

Does anyone have a clue what would cause this. Naturally it works fine in Firefox.

I've gotten several people in my office to try it with IE and they all get the same issue. They all say it works in Firefox.

Answer 1

Just like rymo said set Cache-Control: private, If your response header happen to have the Pragma :no-cache, you also have to change it to Pragma: token .

Answer 2

Based on the KB article David offered here (Internet Explorer file downloads over SSL do not work with the cache control headers), we changed our outgoing headers away from Cache-Control: no-cache to Cache-Control: private. This seems to have resolved the IE8 problem without affecting other browsers. Beware of using Cache-Control: no-store as well.