Occasionally, after I’ve updated a client’s web site, the client will contact me to say that they’re still seeing the old content on their browser, and question whether the updates were ever done. My reply … hit your “Refresh” button!
As we’ve discussed before, your internet browser – be it Internet Explorer, Firefox, Opera or any of the others – typically keeps what’s called a ‘cache’ of recently downloaded files. The classic example is the image that is the logo at the top of every page of Ask Leo!. Your browser will download it once and then keep it in the cache so that on each page that uses the exact same logo the browser doesn’t need to download it again, it can simply use what’s in the cache.
Now if I change the logo, say I update it with a new one, then the browser is supposed to notice that the image is newer than what it has, and update/replace the copy in its cache. That way even for information that changes you always see the most current.
The problem you’re experiencing happens when the cache goes “wonky”. (Gotta love those not-so-technical terms.) In essence, that check for “is there something newer than what I have in my cache” fails, or the attempt to download and replace what’s in the cache fails.
Then you’ll see what you’re seeing: old information.
The top two solutions are actually pretty simple:
- F5/Refresh: about half the time simply refreshing the page will resolve the problem. The F5 key, or refresh, tells the browser to reload the entire page, which causes it to once again check the items in the cache for any updates. (It’s possible that it also ignores the cache, and simply re-downloads anyway.)
- Clear the Cache: about 90% of the remaining instances can be resolved simply by clearing the cache. Depending on your browser, clearing the cache often does more than simply deleting the files. Most caches have some sort of indexing system to speed up access to the files within it. Occasionally, it’s not the files that are at fault, but the index itself that has become corrupt. Clearing the cache also resets this index as well.
When those don’t work things definitely get more mystifying.
I’ll throw out a few ideas, in no particular order.
- Malware: certainly a possibility, as malware – particularly malware that targets your browser – can have all sorts of odd side effects.
- Anti-malware: as silly as it sounds, occasionally the very tools we use to protect us from malware can occasionally have unintended side effects, and this could be one of them. Consider turning off any browser-specific options in your anti-spyware or anti-virus software to see if things change. (Particularly if this system uses different tools than the ones that appear to work properly.)
- Filesystem corruption: I mentioned above that defrag having an impact is really odd, but it does lead me to this suggestion: run chkdsk. It’s possible that there’s a problem with the storage of files on disk that’s preventing the cache from working properly. In most cases, you’re probably running a single “C:” drive, so you’ll need to schedule the chkdsk for the next reboot. In a Windows Command Prompt, enter “chkdsk /f”:
C:\Documents and Settings\LeoN>chkdsk /f
The type of the file system is NTFS.
Cannot lock current drive.
Chkdsk cannot run because the volume is in use by another
process. Would you like to schedule this volume to be
checked the next time the system restarts? (Y/N)
And then respond “Y” to schedule the chkdsk.
For the record, things like cookies, history and the like should have no impact on the symptoms you’re experiencing. This is all about the browser’s cache, and its working properly, or improperly.