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Are Cache-control: pre-check and post-check headers still supported by IE?

I found information that Internet Explorer 5 or maybe IIS 4.0 introduced support for the pre-check and post-check Cache-control headers. I haven't been able to find much info on if they are still supported in later versions such as IE 8, 9, 10 & 11.

I want to remove support for them in an application but want data that they are no longer used.

Solution

  • According to the replies on your tweet from the people that know what they're talking about, the pre-check and post-check headers may be supported, but their use is discouraged.

    (just posting for posterity)

    Yeah, short answer is that nobody should use these and all uses of "p*check=0" are junk.

    I left p*check support in WinINET in the IE9 rewrite & I doubt removed since, but urge you to not use.

    ~ Eric Lawrence, Internet Explorer engineer who wrote the pre-check/post-check header code

    sources: