Internet Explorer cannot download…

“Internet Explorer was not able to open this Internet site. The requested site is either unavailable or cannot be found. Please try again later.”

Seen this before? I have, and I recall it being a bug on IE6. I may have even worked around it in the distant past (and forgotten what I did) but recently I’ve had this error message again.

However, this time I was alarmed to find that IE7 was suffering this error when trying to download a file from a webpage. Previously I understood that I had this problem when trying to download on IE6 over https – still a problem but at least it is only affecting a much smaller % of users.

Few places seem to document a definite solution, only suggesting what ‘sort’ of thing may be causing it. There may be other reasons, but in my case (and I suspect the majority of cases) it is an error caused by IE6/7 (perhaps other versions too?) incorrectly interpreting a header sent when a php session is started. The reason a php session may be started when trying to download a file is of course if you’re pulling the file dynamically out of a database. This problem also only seems to happen over https.

The Solution

Anyway, after a bit of digging I found a solution. Add the following code to your php script before the session is started:

session_cache_limiter('none');

This did the trick for me solving problems on IE6 and IE7. I’ll leave this note for future reference and anyone else with the same problem!