Are all Webcache files equal?

Short answer no! But as always with these things it is not that simple.

Webcache is a file central to IE, Edge and Windows store apps interaction with the web. As can be expected as versions of the operating system are updated these move forward as does the Webcache file.

Since the first version of windows 10 was released there have been 3 major changes. The Webcache file is upgraded to the new structure every time, successfully as well, by my experiences. However these upgrades mean that there is no backward compatibility for the file, so the 1803 Webcache file will not run properly on version 1703. It will run, but there will be differences, mainly with cookies.

On the upgrades cookies have been steadily sucked up from the disk into the Webcache file into various forms. However the old entries will still exist. So it can appear to work over different versions, but the truth is that you are using different cookies for the same website. Double trouble if you like. And being in the Webcache file they are all or partially untouchable.

In 1803 the cookies are completely contained in the Webcache file. There are disk folders with a single ‘.dat’ file, but no cookie files on the disk.

As I said, the answer is never as simple as you would wish.

Simon Thompson (Avanite Developer)