I've been getting this error since the Historical birth, marriage and obituary collection was new. Not with every image but it occurs more than half the time and mostly with dates later than 1960. I've tried all the suggestions posted on this board, uninstalled the viewer, reinstalled, changed the options back & forth, rebooted, even installed from scratch on a newer computer. Nothing has fixed the problem. And there has never been any kind of response to the dozens of reports I've made over the last year.
For the $300 I pay each year, I expect a reply to this post from an Ancestry employee who will tell me that they've identified the problem and what they plan to do to fix it. Paying subscribers should not have to rely on other users for backdoor solutions to Ancestry's problems.

After going through all the above steps *again* with Ancestry tech help, they finally checked out a link to one of the images I can't get and admitted that they can't see it either:

"The image is having trouble and we have reported the problem. They will look into fixing it but I do not know how long that will take."

Experience tells me that it will NEVER be fixed. There are thousands of inaccessible images in this database. How Ancestry can feature this hugely flawed database as a selling point is beyond me unless the people responsible have NO PRIDE in their work whatsoever. SHAME ON YOU.

Geez, you actually made contact with a human being? How did that happen? "Canned" answers are all I've ever gotten to my questions/problems/feature malfunctions/broken links/error corrections/etc., etc., etc.

And those "canned" answers almost never solved my problems. They usually refer me to FAQs.

The answer is you need to check you antivirus protection settings or possibly firewall. For us it was McAfee Antivirus Access Protection \ Maximum Protection:Protect cached files from password and email address stealers: Action blocked. I unchecked this and we were able to view images that we previously weren't able to view.