Web Observatory

ommon problem that is often last checked when troubleshooting a website is the browser cache. What ever your browser is, it uses a cache to store temporary data of sites you frequently visit or had just visited and uses it to display those pages in your browser much quickly.

The problem however is that sometimes, the browser isn’t quick enough to reflect changes on your site. And one of the more common problems when you are a webmaster and you update your site frequently via ftp is that the url doesn’t reflect the current state of the site quickly. For example you uploaded a new stylesheet and you go to the page with that style at www.pagewithstyle.com, sometimes the style change isn’t applied immediately, but when you check pagewithstyle.com without the “www”, it reflects the changes you made.

So one more tip for your book, always clear your browser cache every time you make changes on your online pages and do it first before troubleshooting anything, it will save you a lot of headaches in the future. Instructions on how to clear your cache the quick way after the jump.

Internet Explorer

• To reload a page and bypass the cache:
  • either: Hold the Control key, and press F5.
  • or: Hold the Control key, and click the Refresh button on the toolbar.
• To completely clear the cache (see note above):
  • Click on ‘Tools’ and then ‘Internet Options’ and choose the ‘General’ tab. Then click on “Delete…” under “Browsing history”. In the ‘Temporary Internet files’ section, click ‘Delete Files…’. You will then get a dialogue box asking if you want to delete just the temporary files, or all offline content. Choose the latter and click ‘OK’.
• To change cache settings (only do this if you are reasonably confident of what you are doing):
  • Selecting ‘Tools’ → ‘Internet Options’ → ‘Temporary Internet files’ → ‘Settings…’ allows you to make advanced configuration changes to the cache.
    • There is an option labeled “Check for a new version of stored pages:” This does not bypass the cache, it merely determines how often the browser asks if there is a newer version available.

 Konqueror

• To reload a page and bypass the cache:
  • either: Press F5.
  • or: Click the Reload button on the toolbar.
  • (Unlike other browsers, Konqueror seems to bypass its cache whenever you reload a page.)
• To completely clear the cache (see note above):
  • From the ‘Settings’ menu, select ‘Configure Konqueror’. Scroll down to select the icon labeled ‘Cache’, and click the button labeled ‘Clear Cache’.

Mozilla family

This includes Firefox, Netscape Navigator (versions 6.x and 7.x) and SeaMonkey.

• To reload a page and bypass the cache:
  • either: Hold down the Control key, and press F5. Alternatively, hold both Shift and Ctrl and press R. On an Apple Mac, use the Command key instead of Control.
  • or: Hold down the Shift key, and click the Reload button on the navigation toolbar.
• To completely clear the cache (see note above):
  • From the ‘Edit’ or ‘Tools’ menu, choose ‘Preferences’ or ‘Options’. Expand the ‘Advanced’ options and choose ‘Cache’ or ‘Privacy’. Click the button called ‘Clear Cache’.
  • In newer versions of Mozilla Firefox, you can easily clear the cache, history and cookies: Hold down the Control and Shift keys, and press Delete (or Del), then choose what you want to remove. Or from the ‘Tools’ menu, select ‘Clear Private Data’.
  • For older versions of Mozilla Firefox, go to ‘Tools’ → ‘Options’ and click on ‘Privacy’ (picture of a key) in the sidebar of the window that pops up. Click the ‘Clear’ button that is next to the word ‘Cache’.
• To disable the cache permanently (only do this if you are reasonably confident of what you are doing):
  • Click on the word ‘Cache’ and tell the computer to allocate 0 KB to store the cache in.

Opera

• Reloading a page:
  • Opera does not appear to have an option to forcibly bypass the cache, so if a normal refresh does not seem to work, you may want to try one of the following:
    • Empty the cache completely (see below).
    • Click edit this page, and save the page without making any modifications (this doesn’t affect the page history).
• To completely clear the cache :
  • From the ‘Tools’ menu, choose ‘Preferences’. Expand the ‘Advanced’ options and choose ‘History’. Click the button called ‘Empty now’.
  • Alternatively, you can easily clear the cache, history and cookies: From the ‘Tools’ menu, choose ‘Delete private data’. Click ‘Details’, make sure that ‘Delete entire cache’ is selected, and then choose any other data you want to remove.
• To disable the cache permanently (only do this if you are reasonably confident of what you are doing):
  • From the ‘Tools’ menu, choose ‘Preferences’. Expand the ‘Advanced’ options and choose ‘History’. Click on the dropdown for ‘Disk Cache’ and select Off.

Safari

• To reload a page and bypass the cache:
  • for version 3 or newer:
  • either: Hold down the Command keys, and press R.
  • or: Click the Reload toolbar button.
  • (In Safari 3, “regular” reloads will always bypass the cache. [1])
  • for version 2 or older:
  • either: Hold down the Command and Shift keys, and press R.
  • or: Hold down the Shift key and click the Reload toolbar button. (This may not work in all versions of Safari)
• To completely clear the cache (see note above):
  • From the ‘Safari’ menu, choose ‘Empty Cache…’ or hold down the Option and Command keys and press E.
• To disable the cache permanently (only do this if you are reasonably confident of what you are doing):
  • Quit Safari by choosing ‘Quit’ from the ‘Safari’ menu, or by holding down the Command key and pressing Q.
  • Open a Terminal window by double-clicking ‘Terminal’ within the ‘Utilities’ folder, which is within the ‘Applications’ folder.
  • Type the following commands, which are case-sensitive, each followed by the Enter key:
    • rm -rf ~/Library/Caches/Safari
    • touch ~/Library/Caches/Safari
  • Quit Terminal by choosing ‘Quit’ from the ‘Terminal’ menu, or by holding down the Command key and pressing Q.
  • Relaunch Safari.

Flock

• To completely clear the cache (see note above):
  • Go to the Toolsmenu and click on Options
  • Go to Privacy and then, under Privacy, click on Cache
  • Click on Clear Cache Now