I seem to be having issues with Internet speed, specifically when searching the web. I have confirmed my Internet providers' connection and my router are both working properly. How can I check the computer system itself?
How can I run an overall check of the performance of my iMac - a complete diagnostic to make sure the computer is running at optimal performance?
iMac, Mac OS X (10.7.5)
There are many possible causes for problems with web browsing. Below are some simple steps that may either solve the problem or point the way to a solution.
Back up all data before making any changes.
1. Restart your router and also your broadband device, if they're separate.
2. If you connect to the the router with Wi-Fi, turn Wi-Fi off and then back on.
3. If you connect with Wi-Fi and you can also connect with Ethernet, do that and turn off Wi-Fi.
4. If your browser is Safari, then from the Safari menu bar, select
Safari ▹ Preferences... ▹ Privacy ▹ Remove All Website Data
and confirm. If the Downloads button (with the icon of a downward-pointing arrow) is showing in the toolbar, click it and then click Clear in the box that appears. The download history will be removed.
5. Select the Extensions tab in the Preferences window. Turn all extensions OFF and test. If there's an improvement, turn extensions back ON and then disable them one or a few at a time until you find the culprit.
6. If you're running OS X 10.10 or later, select the Search tab. Uncheck the box marked
Enable Quick Website Search
if it's checked.
7. If you're running OS X 10.9 or later, select the Advanced tab and uncheck the box marked
Stop plug-ins to save power
Quit and relaunch the browser.
8. Enable guest logins* and log in as Guest. Don't use the Safari-only “Guest User” login created by “Find My Mac.”
While logged in as Guest, you won’t have access to any of your documents or settings. Applications will behave as if you were running them for the first time. Don’t be alarmed by this behavior; it’s normal. If you need any passwords or other personal data in order to complete the test, memorize, print, or write them down before you begin.
Test while logged in as Guest.
After testing, log out of the guest account and, in your own account, disable it if you wish. Any files you created in the guest account will be deleted automatically when you log out of it.
*Note: If you’ve activated “Find My Mac” or FileVault, then you can’t enable the Guest account. The “Guest User” login created by “Find My Mac” is not the same. Create a new account in which to test, and delete it, including its home folder, after testing.
9. Are any other web browsers installed, and are they the same? What about other Internet applications, such as iTunes and the App Store?
10. If other browsers and Internet applications are also affected, follow these instructions and test.
11. If Parental Controls is active for any user, please turn it off and test.
12. Open the iCloud preference pane and uncheck the boxes marked Safari and Photos, if they're checked.
13. Are there any other devices on the same network that can browse the Web, and if so, are they affected?
14. If you can, test Safari on another network.
15. Start up in Recovery mode. In the OS X Utilities screen, select Get Help Online. A clean copy of Safari will launch. No plugins, such as Flash, will be available. While in Recovery, you'll have no access to your saved bookmarks or passwords, so make a note of those before you begin, if they're needed for the test.
After testing, restart as usual.
There are many possible causes for problems with web browsing. Below are some simple steps that may either solve the problem or point the way to a solution.
Back up all data before making any changes.
1. Restart your router and also your broadband device, if they're separate.
2. If you connect to the the router with Wi-Fi, turn Wi-Fi off and then back on.
3. If you connect with Wi-Fi and you can also connect with Ethernet, do that and turn off Wi-Fi.
4. If your browser is Safari, then from the Safari menu bar, select
Safari ▹ Preferences... ▹ Privacy ▹ Remove All Website Data
and confirm. If the Downloads button (with the icon of a downward-pointing arrow) is showing in the toolbar, click it and then click Clear in the box that appears. The download history will be removed.
5. Select the Extensions tab in the Preferences window. Turn all extensions OFF and test. If there's an improvement, turn extensions back ON and then disable them one or a few at a time until you find the culprit.
6. If you're running OS X 10.10 or later, select the Search tab. Uncheck the box marked
Enable Quick Website Search
if it's checked.
7. If you're running OS X 10.9 or later, select the Advanced tab and uncheck the box marked
Stop plug-ins to save power
Quit and relaunch the browser.
8. Enable guest logins* and log in as Guest. Don't use the Safari-only “Guest User” login created by “Find My Mac.”
While logged in as Guest, you won’t have access to any of your documents or settings. Applications will behave as if you were running them for the first time. Don’t be alarmed by this behavior; it’s normal. If you need any passwords or other personal data in order to complete the test, memorize, print, or write them down before you begin.
Test while logged in as Guest.
After testing, log out of the guest account and, in your own account, disable it if you wish. Any files you created in the guest account will be deleted automatically when you log out of it.
*Note: If you’ve activated “Find My Mac” or FileVault, then you can’t enable the Guest account. The “Guest User” login created by “Find My Mac” is not the same. Create a new account in which to test, and delete it, including its home folder, after testing.
9. Are any other web browsers installed, and are they the same? What about other Internet applications, such as iTunes and the App Store?
10. If other browsers and Internet applications are also affected, follow these instructions and test.
11. If Parental Controls is active for any user, please turn it off and test.
12. Open the iCloud preference pane and uncheck the boxes marked Safari and Photos, if they're checked.
13. Are there any other devices on the same network that can browse the Web, and if so, are they affected?
14. If you can, test Safari on another network.
15. Start up in Recovery mode. In the OS X Utilities screen, select Get Help Online. A clean copy of Safari will launch. No plugins, such as Flash, will be available. While in Recovery, you'll have no access to your saved bookmarks or passwords, so make a note of those before you begin, if they're needed for the test.
After testing, restart as usual.
How do you run diagnostics on an iMac?
