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It's a good practice to completely clear browser data periodically. To do this you want to be sure all options are checked and choose a time period such as "the beginning of time". If you do not want to lose your download history and/or don't want to have to log back into a site, choose just to clear cached images and files.
Firefox
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Go to “History” in the top menu, then “Clear Recent History”. Uncheck everything but “Cache” then click on “Clear Now”.
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This wiki goes into more detail on how to clear your Firefox browser cache.
Chrome
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Mac: Chrome menu > Clear Browsing Data
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This wiki goes into more detail on how to clear your Google browser cache.
Safari
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Mac: Safari menu > Clear History...
This wiki goes into more detail on how to clear your Safari browser cache.
Internet Explorer:
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Microsoft Edge
This wiki goes into more detail on how to clear your browser cache when using Internet ExplorerMicrosoft Edge.
Additional Resources
- http://www.wikihow.com/Clear-Your-Browser's-Cache
- http://support.mozilla.org/en-US/kb/how-clear-firefox-cache
- ITS Blog - Tips for avoiding malware infections
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