Web Cache
Sometimes your web browser may show old data in web pages.
First, try pressing refresh button in your browser (Refresh button in Microsoft Internet Explorer and Reload button in Netscape).
If this gives you new data, then your web browser is probably OK, and you have just revisited a web page using your web browser’s Back button. You just have to press the Refresh/Reload button when reviewing web pages.
If you believe the page you are viewing should have updated data then you may have a CACHE problem – either in your web browser cache, or sometimes in your Internet Service Provider’s cache.
Web Browser Cache
This means that when you download a web page from a site, your web browser on your computer, unbeknown to you, will keep a copy in its web browser cache in a temporary directory somewhere on your computer. If you need to refer to that web page again, your browser can get it straight from the computer (fast) rather than back over the Internet (slow).
The size of the cache is generally configurable by using the ‘Options’ button and then a subsequent option. You can set it to zero to stop caching and always go the Internet (but normally you would not do this). The browsers perform house keeping to only keep a certain number of documents in the cache so they are not filling up your computer’s hard drive.
Caches are generally good as they do improve performance, especially for static documents (i.e., ones not updated regularly). However, the one time that they aren’t so good is for data or information that constantly changes or updates. If the browser thinks that it has a copy of a requested file in its cache, it may not go back to the Internet to get a new copy. It will just use the local cached copy on your hard drive. For highly dynamic data, this is bad and this causes old data to be shown instead of new data.
Technically, the browser can ask the server for the date of the last update of the requested document and use the local copy if it is the same age or download the document if it is newer. Most browsers do this properly but some browsers do not.
Suggested Solution
If you feel a web page is old and is not updating when you do a normal refresh/reload, then do a forced-reload (shift-refresh for Microsoft Internet Explorer and shift-reload for Netscape) and you will force the browser to go to the Internet to get a fresh copy.
If you now see a fresh version of that page, you can assume that your web browser cache was causing the problem. Please check your browser cache settings to see if you can fix the problem. For Microsoft Internet Explorer, click on TOOLS and select INTERNET OPTIONS. In the GENERAL TAB, you will see “Temporary Internet Files.” Click the SETTINGS button. Where it says, “Check for newer versions of stored pages” choose “Automatic”. If no such option, choose “Once per session” or “Every visit.” For Netscape Navigator users, click EDIT, then PREFERENCES. Open the topic ADVANCED and click on CACHE. See “Document in cache is compared to document on network.” Click “Automatic.” If there is no such option, choose “Once per session.”
If you are doing shift-refresh/reload and you still cannot get fresh versions of web pages, then you may have an Internet Service Provider Cache problem (see section below).
Clearing the Web Browser Cache
Especially with caches that are large in size and nearly full, the mechanics of downloading an image or file, finding room to insert it into the cache, and then actually looping it within a fixed time can prove too much work for some browsers. In such circumstances, the end result can be that only the ‘please wait’ message is displayed while downloading activity continues. A solution is to clear out the browser cache. This substantially reduces the work that the browser must do and gives it a chance to display the image. An unfortunate consequence of this is that all of the images and text must be downloaded again for all sites (and that ‘working offline’ has nothing to display as it uses the entries in the cache), but it can clear problems such as not seeing the update information at all.
Internet Service Provider Cache
In the same way that your web browser has a cache of recent web pages, your Internet Service Provider can use the same strategy and may be doing the same on your behalf.
In some (rare) cases, even though you are using shift-refresh to get fresh web pages from the Internet, the pages still seem to be old. This may be because your Internet Service Provider also has a cache and their cache may not be set up quite right, and they are not downloading the latest web pages themselves.
Suggested Solution
This is a little harder to fix and you will have to communicate with your Service Provider carefully explaining the problem. He/she should then may be able to fix it for you.