I spent hours today trying to make IE 6.0 less intelligent. I.e., to get it not to cache the AJAX responses.

The first attempts, to include

in the head portion of the HTML sent back to the client was laughed at by IE 6.

So, I use a search engine called Google to assist me in finding what the problem could be.

The first thing that Dr. Google told me was that IE 4 and 5 handled my pragma as if it were

and then the kind doctor went into delirium, mumbling about "needing Expires anyway", "not in IE6", "if Expires=-1, it does cache but immediately remove it from cache" and finally went totally incoherent with something about a 64k buffer being involved and that IE only cared about the pragma directive in the last such buffer filling.

Ok, I tried to follow his incoherent advices by putting the pragma both before the HTML body and after. Yes, you heard right! My response then looked like:

Of course this did not work.

It turns out that - at least in IE 6.0 - you need an HTTP header, a pragma will not do!

So, what did work was to set the HTTP header Cache-Control to no-cache. Remember this next time you use AJAX with MSIE.