Usually it's a matter of cleaning it out, any programmes you don't want or will never use uninstall them, that's as long as one programme is not an element of another that you do need. Defrag the HD will also help. If you find that web pages and sites are slow in loading this can be quite normal and there's not a lot you can do to speed them up, the reason they are sometimes slow is the amount of 'adverts' that the page contains, you can speed them up a little by clicking on the little arrow 'AdChoices'and filter them out. Also set the PC to delete your browsing history on exit by clicking the 'tools' icon in the top taskbar whilst on the 'net' and in 'general' check the box or circle 'delete browsing history on exit'. Disabling 'add-ons' can also help, again, tools>manage ad-ons. Your internet security programme can affect speed when it is running updates and scans but there's nothing you can do about that. I'm sure others will give you some more suggestions.
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