ERR_TUNNEL-CONNECTION_FAILED ERROR MESSAGE

I sell ebooks via the Adobe Digital Editions platform.  However I'm now having customers contacting me saying that when they try to download the ebook link, they get the following error message ... Hmm can't reach this page. It looks like the webpage at XXX might be having issues or it may have moved permanently to a new web address ... ERR_TUNNEL_CONNECTION_FAILED.  I'm reading that it's because they are using Chrome. Can you please fix this. As I'm sure you can appreciate, I can't just ask every customer who uses a Chrome browser to undertake a detailed process of configuring their computer proxy server or DNS just to download and access my ebooks.