Why can’t I see the changes Datasearch has made to my website?
The most common cause and solution:
‘Caching’ is a system used by computers and networks that allows them to store ‘old’ versions of web pages for a period of time. This allows the computer to display the cached (stored) web page rather than take the time to request and display pages from the internet every time they are requested. This is usually only done on pages or information which do not change on a regular basis, so this ‘old’ version is still likely to be the latest version when it is displayed.
If clicking the refresh button (on your browser toolbar) doesn’t request the latest version of the page from our servers, you can try a ‘full refresh” by holding down control and pressing F5 or try looking at the page from another computer which isn’t on your network. If you still cannot see the latest version of the page, then it is most likely an ‘upstream provider’ in your office network that is “caching” the page on their servers. This issue is explained further below.
Please contact Datasearch if you require further assistance with viewing changes to your website.
Explaining more complex issues
Caching issues caused by ‘upstream providers’
On the Datasearch server, where your website is stored, the ‘caching’ (also known as page expiration) option is set to ‘automatic’ which allows upstream providers (that is, computers within your office network) to decide what information will reload every time, and what will not. This setting we have on Datasearch servers is industry standard practice and most web servers worldwide are set to the same.
The network set up in some offices may therefore sometimes create caching issues where you cannot view the latest versions of some pages on the internet. Commonly, networks that receive a large amount of internet traffic, may ‘cache’ pages for a day or two (especially pages or information that don’t normally change very often- such as PDFs and Menu bars etc). Keeping a local copy of the ‘old’ page ‘cached’ on the office servers / computers saves such offices a large amount of download time (and in turn money as they save in bandwidth costs), and also speeds up internet access.
For example- if you click to download a PDF file, instead of going all the way back through the internet to the Datasearch web server (where your website is being stored), it may simply get the latest ‘cached’ version of it from your local office server (which is much closer) or even off your local computer. As a result of this, you may notice some of the changes to your website are visible, but some changes, such as changes to images, menus or files, may not yet be visible.
In the same way, Internet Explorer, caches (keeps a local copy of a page/file you have previously requested) so that if you go to the website again within a short period of time, Internet Explorer doesn’t need to re-request the page / file from the internet (therefore speeding up the time it takes to load the page again). You will find caching options under Tools | Options | Temp. Internet Files | Settings.
The options are: “Check for a newer version of the page…”
(a) every visit,
(b) every time you start IE,
(c) Automatically, or
(d) never.
Generally, this is set to ‘automatic’, which leaves it up to the computer to decide which files to re-request from the internet, and which files not to display a cached version of. But you will note that there are various options even within your own computer that can affect whether or not you can see the most recent version. This is why there is a “refresh” button in your Internet Explorer program- (If caching worked 100% of the time, there wouldn’t be a need for this refresh button).
If there is a file on a website that is expected to change very often, then special options can be set on Datasearch servers to tell all downstream systems to request a new version of a file every time, and this may eliminate some extreme cases.
Please contact Datasearch if you require further assistance with viewing changes to your website.