Your browser's cache keeps a copy of an already visited website on your computer to provide for faster loading the next time you visit that site. However if your cache is never refreshed, the cache contents can be out of sync with the rest of the site. This can create errors.

We have recently modified our site's software to provide for faster response. Please make sure to set your browser's cache-refresh frequency to every visit so that you always get the latest version and avoid errors.

Note that checking a site against the cache means that it will load the latest version only if the content is more recent than your cached copy. You will still benefit from faster loading on all the parts of the site which haven't changed since your last visit.